Hai Dr. I Really Hv A Severe Issue In My

Hai dr. I really hv a severe issue in my mind. Thts me boyfrinds issue. Befre 10 months ago he had sex with a girl when he was in the ship. Bt he has used condoms as well. And aftr coming to his motherland he did all the tests regarding to STD and the reports were negative. N he has got a new shaving machine from a friend n he has shaved the area around penis n aftr tht he has got some blisters. Day by day blisters are increaing dr. So i want to knw whethwr it is due to sexual contact or due to shaving.if u want dr i hv the photo of it also. Blisters are very small. Plz doc answer me