Razor Bumps or STI

I had unprotected sex with another girl, other than my girlfriend (my girlfriend is clean and has been checked), however I am not sure about the other girl.  I haven't been checked, but have scheduled an appointment.  A few weeks after I started to notice bumps on the base of my penis on the right hand side.  They are not itchy, do not puss, and it just seems as they are like skin tags.  I try not to shave over them to irritate them but it is hard and when I do they bleed a little but don't cause pain. They have been there for approximately a month and have not gone away on their own.  I shave my genitals regularly but this is a first for me.  If you are able to enlighten me on this situation it would be greatly appreciated.

Thanks