Hair falling out!

Hi i was wondering if anyone else is having the same trouble as me. I was having a shower this morning washing my hair when loads of it starting coming out i'm not talking a few strands i'm talking enough to make a mini me! Anyway i'm 16 weeks and thought my hair would be glowing as it was with my son but how wrong could i be! I was given steriods by the a&e doctor yesterday for my ashtma so been taking them two days now could they be the problem this early into taking them?