What are my chances?

I havent been on birth control for a few months. My boyfriemd and I had intercourse Saturday night, and we didnt use a condom nor did he pull out. The next day I got the Next Choice pill pack. It was two pills, take one and then take the other 12 hours later. I took one because I knew that is what he wanted me to do, but then we read all these bad health risks that comes with it, and I felt so bad about the choice I made. I always told myself I would never have an abortion, and even though technically it isnt ‘abortion’ it is to me, so he flushed the 2nd pill down the toilet before I could take it. How likely is it that I could be pregnant?