OP YANBU, i could have written your post in March... adding in pregnant and not home till 11.45, having left at 6.30. Guess what?! City lawyer too!
He did call during the day to apologise and i know he felt bad, he bought me a pot plant (?!) yes really which he gave to me that night. I was so upset i hid in the loo and cried and cried- a bit like you, my birthday is on the same day every year, could you not have organised something in advance rather than grab the quickest thing in a panic on the day?
Have you spoken to him about it? Asked if you could do something nice at w/e together? I would tell him you are hurt that he couldn't get back in time. My DH is a lawyer, my DF is still a lawyer, and contrary to other posters i get that it is a devils bargain- you get well paid for it but there are no half measures. The client is king and if they want it doing now, it gets done now. My DF is about to retire. He does a very specialised type of law, which v few people can do. His firm want him to stay on (late 60's) and he said he would love to if he could do it 2 days a week etc, but it is just not possible in this type of role. So i suppose what I'm saying is i disagree with some posters saying that it is him being selfish/workaholic/about his ego.
Depending on his level etc, exactly what it is he does, I would assume it is take it or leave it- no half measures. Maybe you two need to sit down and work out whether this career is what you both want for your family, would you both be happier doing something else? Can you afford to? My Dh dislikes his job- not the work so much but the 24hour, client arse licking nature of it, but right now we can't afford to take the HUGE financial hit for him to change careers so I try and not take it personally that I maybe see him for 20min a day (i stay awake to say hello, he has a shower and collapses into bed, that's it).
So after a bit of a waffle, no you are not unreasonable at all to feel this way. I really would try talking to him about it in a non accusatory fashion, and certainly if he is like my family, and friends of ours who are city lawyers, it is NOT about his ego/lack of care for you, it's how the job is, and what is expected of him. Good luck