Having a baby?

I'm 19 and in my sophomore year in college. My fiancé has graduated college and is now working. We really really want to have a baby but I know I have to finish college. I'm taking birth control and he doesn't know so now he feels as if his swimmers don't work. He blames himself for me not being able to get pregnant yet. I just don't think I can tell him I'm on the pill. Should I make myself and my fiancé happy and decide to get pregnant and forget about college where I'm unhappy and confused? Or should I just finish up these two years and think about kids later?