my god, I didn’t want to make a big deal of it
Your actions suggest you do want to make a big deal of it though. You made your annoyance clear enough that your husband had to keep asking you what was wrong.
Then, when your husband (understandably) had had enough he got angry.
Then, it was a big enough deal that you came on here looking for validation. Unfortunately, you can't accept that 84% of us think you are unreasonable.
Unfortunately I’m not a robot and I cant just switch my feelings on and off.
You don't have to be a robot to relegate your feelings and behaviour. Non-toxic people do it all the time.
how in your opinion is the best way to deal with it?
Get some perspective on what is important and what is not. If it's not important let it go. If it is important talk about it honestly and openly. Don't use silence, sulking or refusal to discuss what is bothering you as a weapon.
Be honest with yourself and think about why your husband and 84% of people on here think you are unreasonable.
You, your husband and your children will be happier and more settled if you deal with conflict appropriately.
I was then trying to settle them for bed and the youngest wouldn’t settle until he returned at 9.30 asking where he was.
Why couldn't you just tell him Daddy's gone out for milk? Then he wouldn't have to keep asking. Did he sense your annoyance and feel unsettled by it?
Takes 2 seconds to walk up the stairs to tell me.
I obviously don't know why he didn't do that, but he did phone you shortly afterwards (15 minutes?). That doesn't seem unreasonable to me.