Hey Doc, So Since I Were Having Sex With My

Hey doc,
So since i were having sex with my girlfriend, she started to have pain while we had it.
Whenever i didnt wash my penis after sex it would have red bumps and was itchy, so i'm pretty sure its balantis.
The red spots are gone now because i put my penis in water with vinegar in it, and haven't had it ever since. but theres still a spot on my penis that is highly sensitive and red, and in rare occasions it can be itchy. So i'm having some doubts about whether its bacterial, or fungus.
I should also add that my girlfriend uses daktacort, and so do i.

I thank you for your time!