What Causes Brown Bleeding Every Time After Sex?

I noticed one day after my period that I was spotting brown blood. It lasted a couple of days. Then, it stopped. A couple weeks later I had intercourse with a new boyfriend, he did ejaculate in me, (trying to have a child) but once i went to the bathroom I noticed brown blood everywhere, it was on him as well. Every so often I will discharge/spot brown blood but its not often. However every time we have had sex since then even when he pulls out the brown blood still appears, it began after my period last month, I've had another period since, and it has continued now that I am off of my menstrual cycle. Sorry for all the TMI, I'm just worried, and its kind of embarrassing. Could something be wrong? If every time I have sex this brown blood appears?