HIV risk?

[akpflow]

Around February 13, my friend and I went to the Laboratory to run some tests including HIV and Hep B. All the tests were negative for us then we had unprotected sex. After four weeks, I noticed rashes on my arms especially on my left arm. I ran a rapid HIV test after 28 days which came out negative. This is rash is still on my arms (small bumps and dark purple spots).
I'm really worried about this.

Any thoughts on this?

[CurfewX]

I have no idea why you are asking about your rash in an HIV forum, when HIV is the ONE cause you can definitely rule out, since your tests prove that you don't have HIV. A rash on the arm isn't even a symptom of HIV.

See a dermatologist for evaluation of your non-HIV related rash.