Bleeding after sex (maybe TMI)

I’m 6 months pp and have been spotting a little here and there, very minimal and mostly brown tinged. Just had sex last night (not the first time, but we haven’t frequently had sex since the baby was born) and now I’m bleeding slightly more, red blood though. I haven’t had my period since the baby was born, do you think this could be the return of my period or do you think this is sex related? I did notice last week or the week before that it seemed like I was ovulating but again I also had slight brown tinged discharge as well.