I don't care about my actual birthday but I do care about everything that surrounds it, just by age people assume a lot about you and determine what you're allowed to do or not.
It's important to realize how others look at you, whether you care or not is up to you.

As for celebrating the actual birthday, I do enjoy it.
Birthdays in my family are always a social happening and all of us come together and have a good time, chit chat and get updates about how their lives are going.
I always find it quite interesting to interact with them.

As for presents... you might see it as selfish to enjoy receiving presents from your family or friends for your birthday but don't you also give them a present for their birthday as well?

Doesn't seem selfish to me like that.