Okay, sorry for the inevitable TMI...

I last had sex somewhere around November 25-30. Then I had a heavy but short period that started December 4th. Starting yesterday, so around a week later, I've been having random spotting. I am on the pill but (again, sorry for the TMI) had diarrhea on the 24th, so I'm paranoid that my pill wasn't digested properly or something? Pregnancy isn't anything to be concerned about right now, right?