I cut my head but not deep however some significant amount of hair came off I'm only 17 I'm really scared I don't want to lose hair will it grow back ease help ?

Is it still bleeding or oozing blood?You probably should have a doctor look at this in case it needs a stitch or two. Losing hair and having a bald spot would be the least of my problems right now.

If you fell and hurt yourself you should see a doctor immediately, especially if you tore off some of your scalp and/or hair!

I agree, and also there is no reason why your hair won't grow back.