I used an oral hiv home testing kit last month it had only been 3 months it came up negative should i worry about hiv?

HIV is hard to get: You have a 95% chance of being fine with that test. If you want to test again you should. But, if you have any high risk exposure remember you can prevent the infection in many cases if you act within 72 hours of the exposure. There is also an HIV test for the dna or RNA that closes the potential window down to 21 days post exposure for an accurate test.