STI symptoms??

Ive been seeing this guy for like 1-2 months now. I am also on the pill and have been for about 5 years now. My last period was April 24-28 and I started a new pack April 26. on April 29 we had unprotected sex (and used the pull out method). for the last week and a half I have noticed a little cramping. my discharge has been abnormal, a little thicker than usual and also a lot less than how much i usually get. I've noticed a stronger odor too, not necessarily fishy but there's definitely an odor that's not always there. I have also been feeling a little fatigued too. I am now on my third week of the pack and I've been spotting. for the last year I have been spotting on the third week of my pack, but this time it's a lot more too. I have had sex since and afterwards I've been getting yellow/green/tan discharge as well. Do you think this could be a STI or some kind of infection? or maybe even pregnant ??