About a month ago I hooked up with this girl in bed, but did use a condom.
Ever since we hooked up I've been having these rashes or bumps that itches around the inner thighs. Could anyone tell me what's going on?
Please tell me it isn't an STD.
What could help to get rid of these rashes/bumps?

No one can say for sure if its an STD you will need to go see your doctor...
It may be from over rubbing from having sex..
But other than that I can't think of anything for you but a doctor sorry