A newbie birthday! And you share it with my oldest son, so doubly col from my point of view.
However it brings into focus your story of the RSI when I see you are only 19!! Good lord, I'm twice that age and I'll be honest, generally I've never felt better.
I have top sayu I did have many more twinges and pains at that age too. Funny thing.
I had a looooong course with physios and osteopaths for a shoulder/neck problem, that in the end went away.
Anyway, rambling on. Happy Birthday!