Is dating a guy younger than you weird?

Ive known this guy for about a year now and recently I've been talking to him more. He just turned 16 about a couple of weeks ago and I'm 17 going to be 18 in May. At first I didn't really like him and just thought of him as a friend but lately he's been there for me and treating me so well that I just sort of began thinking he must really care if he's been around this long. Some people think it's weird for a girl to date a guy younger which I understand but age is just a number right?! Is it too weird?! Advice plz.