Could I Be Pregnant?

My husband and I had sex a couple days before my period started and we knew he got some come in me. My period came as scheduled but it typically lasts 8 days but this time only lasted 3 and ended with a lot of old blood. Is it possible that I could be pregnant? The timing was just odd and I'm not really worried about it, I just want to know if that would be a possibility since it happened so close to the start of my period.