Why are there redness, inflammation and swelling in my glans penis after intercourse?

Hello doctor,

I hope someone can help me. About 20 days ago, I started feeling pain after sex. I noticed part of the glans penis and foreskin (near frenulum) is red, inflamed, and swollen. I thought the problem could be caused by the hard and vigorous sexual acts (protected sex) I had in the previous days and weeks. I received oral sex (without condoms) with some girls in the previous days or weeks.

In the 1st case, the friction of sex could have irritated the skin of my penis. In the second case, I guess the pain and the red spots could be related to infection (bacterial or viral). The first doctor I visited (general practitioner) told me to apply Canstean cream and use Ciprofloxacin to treat urinary tract infections. After two days, I felt sick and pain in the testicles. Also, the cream did not improve the condition of my penis.

So then I visited the urologist who told me to interrupt Canesten and Ciprofloxacin and to use a Zinc oxide cream. I applied that on the foreskin and glans. After two days the problem got worse because the cream was too thick and I felt pain just touching that area. I called the urologist who suggested me to stop with that product and use a cream that contained Chlorhexidine. After one week, the problem was not solved. The urologist suggested me to contact a dermatologist, and that is what I did. He noticed just like a cordon in the foreskin, near the frenulum and so he told me to apply advanced cream that is a topical corticosteroid for two weeks. Moreover, the doctor prescribed an echo to check the cordon. The echo was negative. Even if I was told, this examination is not complete. I should have done a penile ultrasound with a penis in erection. Next week I consulted a dermatologist again, but the situation is still bad. What can it be?