Oral..

I've always been terrified after doing ANYTHING that I'd be pregnant even if I knew there was no chance. So 2 days ago I decided I'd try oral. He came and I swallowed, yada yada, but I had a cut/sore from where I bit my lip too hard. Yes I know about STD's and I know you can't get pregnant from oral, but what if it got in my cut and into my bloodstream. Obviously blood gets to your uterus and stuff because of periods. So could I be pregnant or do I just need to tell myself to quit worrying so much? Help PLEASE!!!