Is it possible that I'll still get pregnant.....

My cycle has been on continuously for a while. I'm talking about for months none stop. The day that it decided to start spotting, I took advantage of it and had sex with my SO. He let "go" inside me so I was wondering is it possible I could have gotten pregnant from that incident? Sure I know that you can still get pregnant on your period but will it lighten up if the egg is fertilized? It's too early for me to take a test but I also don't want to get my hopes up too high