I have 3 open sores on the base of my shaft?

So, I had with a girl about 4 months ago. The next day she tells me that she has genital but no current sores. Of course, we don't go out again because I feel pretty deceived. I haven't had any symptoms on my during this time. Two days ago I notice a little soreness as I am getting out those last few drops of pee. I look at the base of my shaft, right on the vein that goes up the center of it (about 1/4th up from the bottom). They are mildly tender. They happen to coincide with a farely rough, un-lubricated masturbation session. These sores are somewhat sunken, not surface level, and small. I didn't notice any pain before they were there, such as a blister. I hope to attribute them to friction. What do you think? Are sores just surface and not sub-surface? I'd call them 1-2 mm. One of them seems to be healing faster than the others. I've been to the doctor for "ghost" symptoms and two blood tests showed no sign of .