I have problem with erection after using penis extenders. Have I done irreversible damage?

Hi doctor,

About four years ago, when I was self-conscious about the size of my penis, I started looking into ways to increase the size of my penis. Never long-term, but I tried penis water pump and penis extenders. A few times that I used the penis extenders, the ring may have been very tightly packed around my penis while I was using it and due to the stretch it caused, and tightness, I lost circulation to my penis tip to a point the tip went numb and cold. After that, I started noticing my erections are much weaker and sensitivity has gone down significantly. Besides that, I also became very self-conscious and psychologically worried that I may have made my ED worse. I did not have problems getting an erection, but maintaining one was more difficult and my erections were softer. I stopped having sex. After three to four years, when I masturbate, the quality of the erection is much better and I am able to keep the erection but the sensitivity is not quite back. Also, my climaxes are much weaker and they do not feel as good. In the last year that I have masturbated, I have not had issues maintaining an erection when I am masturbating but I believe the sensitivity is not back. I am worried having sex, I will begin to lose the erection fast. I have red skin marks under the skin at my penis tip that is not going away. Is this due to dead cells? Have I done irreversible damage? Is there any treatment as I now am hoping to become sexually active? Many of my problems are from using the extenders and penis pump aggressively even though it was short usage and regretful decisions.

Thank you doctor,

But I have experienced ED having intercourse four times. My sensation and sensitivity has gone down dramatically. You cannot see it clearly in the pictures, but there is purple skin under the head which I have read could be dead cells as when I was extending the penis head lost blood circulation to the head for extended time and damaged the tissue.