Of course it is shallow. But it can be OK anyway. A bit of vanity is present in most of us. You don't need to fight it, it is fine to embrace vanity as a hobby or profession.

If the baldness goes beyond being a minor nag in your vanity though, and you start believing that regrowing your hair is truly essential to your happiness and wellbeing, you should perhaps seek professional help for your mind rather than your scalp.