Do i have hiv or herpes? a week ago i kissed a guy and two days later my mouth itch, then my gums started aching two more days later. im a virgin

Unlikely: You don't get HIV by kissing. Herpes infection possible by kissing, however it does not happen in two days after kissing.

Go see: Kissing will not transmit HIV. Herpes can be transmitted by kissing, but it's too soon for signs/symptoms to be evident. So go see your Dentist to determine the cause of your concerns. It may be gum disease, allergy to food/Med/supplement, response to GERD, and many other possibilities. See your Dentist.