I've been take birth control for years & I usually get my period at the end of the month. At the end of March I never got my period. (I didn't have sex since January) I did however have sex a week after I started my new month pack of pills for April. I'm now 3 weeks into the pack and still dont have my period. Its been almost 2 weeks since I had sex, and now I'm getting dirreah about every other day and my lower abdomen hurts. Could I be pregnant? (I haven't had any completely missed pills, I have taken a few 6 hours or so late a few times before)