I sympathise, OP. I had the AZ in February before any hooha about side effects (or clots - the reason I got the AZ early was because I'd had a clot a couple of years ago

). I was very grateful to get it but I had an extremely unpleasant reaction and I have put off having my second dose. Doesn't seem to be any option to have the Pfizer this time instead either, so now I'm between a rock and a hard place if people are only going to be allowed to do certain things if they've been double-jabbed.
I had been too blase really the day I had mine, thought anyone complaining of side effects or feeling off was probably just a wimp or in poor health or something. (I haven't had a day off work sick in 4 years and before that just once for a hormonal migraine related to the pill and not for a long time prior to that.) Even when I started feeling very shivery that evening I put about 10 layers on including hats and thought it was quite amusing and thought that would be the extent of it. I even took a selfie of me smiling in all my layers/hats etc as I knew I looked funny and sent it to my mum and sister for a laugh.
I decided to have an early night as thought that alone would do the trick, and thought it was a complete overreaction (and for wimps!) to take any paracetamol so I didn't bother. I really wish I had because I felt so dreadful soon after and for hours. Heart rate of 130 something for over an hour, despite me lying really still, high temp (started sweating profusely and had to strip off all my layers). I just felt so unwell, I haven't felt like that in years and years. I honestly did not expect to feel like that so it was quite a shock and it did worry me a bit till the paracetamol started working as I just wondered how bad it would need to get before I'd need to call someone for medical advice.
I wasn't great at all the next day either, just sat on the sofa as if I was recovering from a virus or an awful hangover. Managed to go into work the day after but felt like a zombie with a bad headache and was pretty useless to everyone. To be honest, the pressure in my temples for a few weeks after was fairly worrying, too, as there are strokes in the family and issues with blood pressure as well as strong family history of DVT & pulmonary embolisms.
So my advice is, just in case you ARE one of the unlucky ones like me, DO NOT drink any alcohol. Take paracetamol as soon as you start to feel you are developing any kind of temperature. Just go to bed and try to sleep.
It does annoy me the way that people who only had very minor reactions or none at all completely dismiss the fact that some people, for whatever reason that no-one actually knows yet, do experience seriously unpleasant side effects.
What's needed is education and support, to provide FULL information, and to look into people's valid concerns a bit more rather than the patronising "ah you'll most likely be fine" and "no, there's not an alternative vaccine and no I'm not prepared to listen to why you don't want the second dose, it's that or nothing."
We're all individuals here. I tend to have inflammatory markers tending towards the high side whenever I have routine blood tests. No-one's ever investigated that as not high enough to warrant it but perhaps that could indicate the reason why I had the over the top reaction the vaccine? Maybe there's actually a subset of people who they'll discover might be more likely to have a severe reaction and could be warned about that so they can be prepared and reassured.
It's really hard when this is all still so new. There are people who are genuinely worried about how their own particular body will react to the vaccine, for reasons often unknown to others. Don't put them in the same group as anti-vaxxers and conspiracy theorists, for god's sake.
I think they also need to send people delaying their second doses a questionnaire as to their reasons WHY, and do their research based around THAT, not waste millions on bloody celebrity-endorsed campaigns. Those are so bloody patronising.