help?

Ja
So, I had sex the other day while I was on my period. It was like, the 4th day I believe and I was only bleeding a very little bit. We did it unprotected because I figured I would still be on my period for another 3 days, because I almost always go for 7 days. But then the next morning I noticed I had stopped bleeding, and nothing since then. So since my period ended early, and we had sex on hr last day, what are the chances of getting pregnant? Keep in mind, my periods normally last longer, and I'm pretty sure I usually ovulate the week following my period. I really don't want another kid right now, I just need some questions answered. Thanks!