You have been already advised that you had no risk. Your urethera was protected with a condom and that ensured your safety.
You are clearly very anxious, your irrational HIV scare is just manifestation of some underlying fear or issue, please see a therapist to find out the original cause of it, sex is a normal thing, it's unusual to freak out after an episode of sex, this is only going to make things difficult for you, see a therapist and address the real cause of anxiety from it's root.
Seborrheic dermatitis is a genetic disease in most cases, outbreaks are chronic, they happen due to triggers, stress and anxiety are certainly one of the reasons for it. Other major reason is change of weather, you have mentioned that you have been traveling.
Please see a skin specialist doctors in your area, where you live. Get ample Vitamin D.
You don't have HIV and you do not need to test.
The condom didn't break and he told you ha was negative anyway.
Your idea that your infection proves you have hiv is your science fiction theory, so it is impossible to have a logical conversation about it - I suggest you talk it over with the doctor who diagnosed your fungal issue or else a therapist instead of trying to find someone here interested in that science fiction theory..