Does Vomiting While On Contraceptive Pills Increase The Chances Of Pregnancy?

I'm on the birth control pill and have been for a little under a month. My boyfriend and I had unprotected sex, and I'm worried about whether or not I could be pregnant. Normally, I wouldn't be concerned, but I've been taking Excedrin migraine medication, and I was sick and throwing up for five days prior to the unprotected sex. I've read that this increases my chance of becoming pregnant. What is your take on it?