Is this the beginning stage of MRSA? Bug bite? Pimple?

I'm an avid gym goer and my boyfriend just recently noticed this... I literally didn't know I had it because I couldn't feel it unless I try to move it around then it hurts a little bit pressure and everything doesn't hurt. I have no idea what it is and I was just kinda gonna wait for it to go down but if it is staph I wanna get it treated immediately. Does this look like an ingrown hair? Infected pimple? Bug bite? MRSA? This is around my armpit so its kind of a weird moist place