DH & I had a weekend in Paris to celebrate my 40th birthday. He arranged it without my knowledge, even arranging time off work with the person I worked closely with. The children, who were 10 & 13 at the time, were in on the surprise and kept it from me, DD reminded DH that she and I had tickets for the ballet (December birthday so part of her Christmas treat) and they managed to get them changed to another date.
Gobsmacked didn't come close!
Having said that, we don't normally bother too much with our birthdays, which fall exactly four weeks apart. When DH turned 65 and I 60 our family arranged some lovely treats for us both but that was more to celebrate the fact that we were both retiring from work around the same time.
I don't think I've experienced any angst about the passing of the years but I dare say that may come in time.