I think you should see a doctor - it does not sound like a self help kind of issue
I strongly discourage you to listen to the comment above. I'm no doctor, but I know one thing for sure. You CAN get STD's from oral sex. If she has herpes and gave you oral, you very well could have contracted the virus. I'd highly recommend going to a doctor or a clinic for some tests.
There is no way you could get an Std like that.
The mouth of a person only carries average bacteria or candida (fungi).
probably the skin just got hurt by her teeth?
Buy a antibiotic cream like Fusidic Acid for example. If it does not heal within a week, show it to your Doc.