Spotting

So it’s been about a month since I stopped my birth control, I spotted when I stopped taking it because the side effects were WAY too much for me. I was supposed to get my period about a week ago, but while my boyfriend and I were having inter course, we noticed some blood. I assumed it was my period but it has been about three days and I am still lightly spotting. I’m not sure if it’s from the birth control or if I could possibly be pregnant. Help please !