...and I don't mean clubbing, necessarily. Find the 24hour eateries around, maybe order a stack of pancakes or whatever mini form of birthday cakes they have going on. We once did a version of this for a friend when she turned 13? 16? 21? (idk, it was ages ago), and got her the same number of cakes as her birthday age, and she had a stack of hams as a cake, a slice of cheese, a convenience store cheesecake, etc etc with a candle on top hahahahha
Play monopoly on the sidewalks. Or cards. I don't know, mini activities like that can be fun. Hang out all night, see the fish or fruits/veg wholesale markets in the morning, and then sleep all of the next day.