Im a people pleaser

From childhood,i feel like nearly everybody dislikes me.Ofc i had a little friend group,but the rest treated me badly.Now im 15,this year i wanted to change myself and i acted like a different person.I gained some friends from it but..I couldn't stand up for myself cuz i didn't wanna be in any conflict.I hated some people in my class but i wanted them to like me.Its very bizarre mindset but I can't do anything.Now it's summer some of my classmates unfollows me or smth.And it hurts cuz what did i do to them?I just wanted to be nice and kind..