I’m 17 and he’s 13, is it okay?

I don’t think so. I mean this type of age difference wouldn’t have mattered if you both were above 18. You’re almost an dukt and he’s basically a child, just entered his teen years. But don’t push yourself too hard and question yourself. It happens. Just try to get over it and don’t tell anyone of your schoolmates. They can be judgemental and move down to shitty behaviour like teasing and bullying. It’s okay you know to feel how you feel, just don’t react upon it or make a move

My schoolmates don’t know it because we aren’t at school because of covid 19. The only guys who knew it are my friends, and they told me that it’s freaking okay because age doesn’t matter just like what others said.