Unlikely to be HIV. You need to stop having sex, until you're better educated about sex and pregnancy and STD's. Most likely you have a yeast infection. That causes, itching/burning down here and can hurt/itch when having sex too...you can also have a white/yellow discharge too. You need to get it treated. You'll need a cream to help with the itching and a pessary or pill to treat the internal infection. Go see your doctor or a pharmacist.
no its not HIV but u need to see doctor to rule out other condition stomach ache may be due to infection of bowel and abt mens u need check for pregnancy test