What Causes Red Cuts On The Head Of The Penis?

hi. my girlfriend was diagnosed with herpes last month ( marking on inside of vagina). she was treated and symptoms have disapeared now. i was tested and it came back negative, although i have never had symptoms. last night she gave me oral sex without a condom. today i have woken up and noticed 2 little red cuts on the head of my penis, although there is no pain, i am not sure if the marks were left from her teeth or i have contracted something. i am little bit paranoid and would love to hear your opinion. Thank you