GRAPHIC PICTURE ADDED BUT NEED SERIOUS ADVICE..

I'm 17 and I have unprotected sex with my boyfriend of 2 years and 7 months. We were each other's first and haven't been with anyone else.. I don't know if this is vaginal herpes or it's just a pimple but I was freaking out about it a while ago too because I thought I had a yeast infection back in September and when I went to the doctor he said it wasn't much yeast in my urine and gave me medication anyway to take.. I wanted advice because I don't wanna over react,it's like a pimple and got a white head and it's on the side. When I press down around that area it don't hurt but it starts to burn,now I do shave down there even when I got pimples so that could be why.. I don't know what to do and I'm sorry it's graphic I just want opinions from people who HAVE this because I know it's a STD that you cannot cure but I don't think you can get it unless your partner has it but he dosent.. I think I started getting my yeast infection after I used a hospital bathroom..