Pregnant on the pill?

I'm on the pill. On May 17th, my bf and I had unprotected sex and while he pulled out, he came a little bit on the outside of my vagina, maybe a tiny bit inside. We've been together 5 years, he's done this many times and I haven't gotten pregnant. My period lasted from May 18th-23rd. Today is the 28th, and the last couple days I've felt some cramping, had creamy CM, and got this ingrown hair on my vag (probs has nothing to do with it but still). I never miss a pill and haven't in over 2 years. What's the likelihood of me being pregnant?