Late period

I was on bc with an IUD for the last 5 years. I recently had it removed and had been taking pills up until August. The month of August, September, and October were normal despite me not taking the pills anymore since End of August. This last month we have unprotected sex but with the "pulling-out" method and having to run to the bathroom on a couple of occasions for the in-case  a little went in. Now I'm 2 days late on my period and my breasts are really sore. I know it sounds silly but is there a possibility I could be pregnant? I think it's just the stress of me thinking that's making me late.