I was in the wrong, AIBU to be disappointed anyway?

Massive overreaction by your H, both the the initial friend request acceptance and in the ongoing sulk.
Do you have children together?
Is he challenged by the fact that you achieve well in the field of work and earn more than him?

A HCP should not be approaching ex-patients online. That's is definitely against code of practice if they're in a registered profession.
That said, I believe your husband is resentful of your success and is manufacturing an argument so that he can undermine you.

Neither of these men come out of this looking great. You need to let your husband know how disappointed you are in him, for a change, see how he likes it.

Your husband is controlling. You can't reason with someone who fundamentally has different values.

I'm not sure where that leaves you, but I wanted to challenge your initial acceptance that you were unreasonable. You weren't.

Fwiw, I think the healthcare worker has seriously breached a professional boundary and should be pulled up on it, but your husband is your main problem.

There isn't really a way to talk this out IMO.

Your DH is an idiot and I can’t imagine how you’ve put up with his controlling behaviour so far.

He had no business complaining to the dr on your behalf and I completely understand why you told them you didn’t give permission for him to speak for you. But… he wasn’t wrong to think the drs ought to know that the HCP is acting like this. I’m sure it must break the terms of his contract. No harm was done by his request to you, but it could be very different if he tries to befriend a vulnerable person he’d met in the course of his work.

Have you kicked off at your husband about phoning the doctor?

Have you told him that you have said you have no complaints and you told the surgery that and confirmed that he has no permission to speak for you?

Because he won’t like any of that.

Gatekeeper to the marriage, keeping other men out, what does this even mean?

He is using your achievement and lack of acknowledgement as punishment. It’s unfortunate timing in one way, but perfect in another.

So now you know what he is really like @DopamineDeficient, he thinks you are lesser than him not an equal. He thinks every single behaviour of yours up to accepting a Facebook friend request needs his approval, which you don’t even know what that covers until after the event sometimes.

And if you misstep, well accept the unreasonable punishment, over unreasonable demands. Know your place, below him, as a service wife to him, as a service human to keep him feeling like king of the golden penis.

This is what you will have to put up with if you stay married. Your choice.

You have the means to leave him, run like the bloody wind.

This

This is shocking!

I wonder if he’s finding something to fall out with you over because you have passed an exam ?

I assume that you now have higher earning potential?

like a sulky 10 year old jealous of his friend.

urgh . Call his bluff. Say it’s a shame he’s so unhappy and maybe you should separate.

then do a happy dance

I think the HCP has broken data protection rules adding you, it’s completely in breech of professional standards.

That aside, your DH is controlling you. Even the fact you think this is all your fault says a lot.

Omg you are not safe in this relationship speaks to someone please your husband cannot get away with this level of control next you'll be barred from going to medical appointments

The HCP was inappropriate, however your husband is a controlling bully.

Your H’s behaviour Is weird and controlling to the point that it’s abusive.

1. Seriously, who would notice that their partners accepted a Facebook friend request within an hour? I couldn’t even tell you how many Facebook friends my DH has to the nearest 100.
2. Not that you should have to justify who you’re friends with on social media, but even when you’d explained who the person was, he carried on arguing about it for “days“
3. Instead of asking you about your exams, he went and checked your phone and checked your emails, that’s not normal.
4. He has made absolutely no effort to celebrate your massive achievement. I bet if this was reversed, he would expect a parade.

I think, if you look hard, you’ll find that he has manufactured a situation where he has an “excuse” to diminish and ignore your massive achievement; and if you look really hard, I suspect it’s not the first time.

You weren’t in the wrong initially you’re not in the wrong now and you deserve better.

The HCA friending you is creepy and so is your husband's phone policing. Do you have a history of poor boundaries with weird men? Take your qualification, get an awesome job and set up home on your own!

I think it's the other way round he found something quite small and unimportant, a new FB friend, and used it to undermine a significant achievement.

Just to add I also think the Health Care Professional is odd who does that? Surely even using a patients name to track them on social media is a data protection breach.

I hope that you will feel able to go out and celebrate your great achievement with people who care about you. Your husband doesn't actually need to be there. . .

(Your new qualification will lead to a higher salary. Men don't always like that. You will have more opportunities, oh dear. And you accepted a friend request from a younger man! From your husband's pov - a near perfect storm.)

The language you use in your original post shows that you've been conditioned to take the blame that your husband heaps on you without question. He's controlling and abusive.

I’d be more worried about him realising you added a new friend. That’s not normal AT ALL.

Yep!

How would he even know you had a new Facebook “friend”? He sounds absolutely controlling and horrible.

Sorry, your husband is checking your phone for friend requests and exam results?!

Get rid.

Agree with all PP. First, you weren’t “wrong” to accept the friend request, second even if you were, your DH doesn’t get to punish you for your perceived misdemeanour as if he is in charge and you are the subordinate, third his jealousy and paranoia are out of control, fourth why is he checking your phone you aren’t a teenager, and fifth how dare he ruin your joy in your achievement and fail to celebrate your success. You deserve much better. Change your phone password and if he doesn’t like it, bad luck.

It's nuts. My husband wouldn't realise if I added a person to FB and he wouldn't care. It's FB!