baby making !!!

So I've been trying to get pregnant for the last 3 months , I was on the depo for about 2 years & my last shot was June or July .. I'm trying to not get my hopes up but every time I don't get good results I end up getting sad and disappointing.. any advice in how I can just enjoy trying to make the baby and not stress to much about it ! ??? I just really want to give my son a sibling ....