I made a female wizard. Sometime before meeting Deckard Cain I learnt a few defensive spell, frost nova, which I could use.

I then made a male wizard to see if I preferred the male character, but lagged soon after entering the dungeon and the frost nova spell never enabled itself. I went a level or two past and the 'lock' has disappeared on the spell bar where frost nova is for the female, but there is nothing there I can select. Has this bugged out?