I do have empathy for you and I can see why you were fed up. Weddings are tiring especially when your are pregnant and caring for a 4 year old. I've been pregnant 3 times and have no patience for when my husband drinks during those times. He's not a big drinker or anything but its just annoying (and I dont like missing out). But I can recognise its partly due to pregnancy!
I certainly can see how this would have ended up as an argument about him getting carried away but it should have just been that then the next day some tired hungover apologies.
However I think you were being really unreasonable invloving anyone else and particulary his family at a family event.
You took your son up to bed so he assumed you'd both be sleeping he can let loose and enjoy time with his family.
You offered to take someone's child up to the room to mind then then only 40 mins later demanding they come and take the children away. Why offer in the first place? Just let the child sleep in the pram and snooze beside them until they are collected.
Your son is four and inconsolable? Let him watch TV or something for a while and relax with a cup of tea. Its not the end of the world for one night, routines are out the window anyway.
Ring down and ask reception to have water sent up as you are with a sleeping child if there is no water in the room or you don't want to drink the tap water. I do understand this one as find hotel rooms (especially in Ireland) so stuffy so I always have extra water.
But I do think you have embarrassed him and the phone calls alone would have been the talk of the wedding. Sending him to someone elses room for getting drunk. Now they hage an extra person in the room that they probably paid alot for not fair.
Im Irish so perhaps there are cultural differences that I am not aware of here but you were over the top.