About a week to ten days ago I went to my doctor for what I thought was a minor cut or abrasion to the tip or just inside the tip of my penis. He looked at it real quick and advised that's probably what it was. He prescribed and antibiotic called SULFAMETHOXAZOLE(for 1 week). I told him that I do not have any swelling or any sores with puss coming out, but I do have pain when I urinate only at the very tip of my penis. I since have completed the medication and the pain has subsided almost 90%, but I still have a littl pain and slight irritation on the tip. Should I be concerned or should I re-new the prescription?