What Causes Persistent Ulcers At The Urethral Opening And Sensitivity During Erection, Despite Treatment With Antibiotics And Ointments?

Hello Dr 3 years ago my penis foreskin got wound by my nails doctor gave me flutibact water base ointment but after using it foreskin wound recovered but i got small small ulcer inside my penis tip i mean in the opening of uthera. Initial time if i do urine it was feeling like someone using blade to cut it. Doctor gave me doxyline, Tao - 100, Herpikind but i didn t get any relief from these. My foreskin is completely clear but still my uthera opening having the wounds it s not like going n coming, it s there from long time with same size it didn t increase as well. Now bcz of this blisters m feeling more sensitive on my penis if i get erected. Kindly help me on this.