HELP WTF IS THIS

I don’t understand., is this my period?! I had unprotected sex about 1 month ago and I still haven’t gotten what to me is a normal period just light spotting or this!!! But this only happens for about 1 day then goes away and it’s horrible cramps too!! I got this same exact thing 2 weeks ago,, I have my app tomorrow to be seen by planned parenthood thank god but ladies I would appreciate some ease at kind before my appointment.... I wipe once and this happens but by the second it’s gone and just light pink/brown ........ what do you guys think it is from your knowledge or experience... 1) period 2) in pregnant or 3) STD