Blisters on the Penis not getting better with ointments

Dear Ask The Doctor: A week ago I had some soreness on my penis. T was irritated but not painful. As I walked for my job my penis rubbed in my pants all day and it irritated me. When I returned home I had a quarter sized water blister on the head of my penis and another smaller one on the shaft. It was really annoying so I pin pricked it and drained them both. The next day I took a hot bath and the skin came off leaving a large red burn like sore. Its only painful when friction in my pants causes rubbing. I did some research online and thought maybe it was a yeast infection. I rule out std, I am married and I've had the same partner for 10yrs now....no symptoms before now. Not possible that its a std. So I applied yeast infection creme...no results. Neosporin...nothing. I need help with this. I have no other symptons, no pain when not walking and rubbing. No pain when peeing. No other symptoms. Please help

Dear Anthony: It is difficult to diagnose the cause of the blister on your penis from the limited information. You have informed that medication for yeast and antibiotic ointment have not reduced the ulcer, suggesting a viral pathology. It may help to get and test for infection from STD to rule out any underlying infection. Also wearing loose cotton undergarments and keeping the area dry will help in most cases.