My postural kyphosis is around 55-60 degrees. I'm 20. Is it going to get worse as I grow older? Is it bad for my health? Should I get concerned?

That's a lot. The main concern is respiratory as the kyphosis may increase in time. Now u should have pfc's and c if u already have compromise ; how much. U may b worse than u think. C a spine surgeon 4 evaluation, if u start there he/she would most likely get ptc's as part of the work up.