Welcome to the Forum. I'll try to help. While the timing of your current illness, three weeks after the exposure you describe, and your symptoms are certainly suggestive of early HIV infection, the odds are still very much in your favor that this is not HIV. Most women in Brasil do not have HIV, you used a condom, and surface contamination to menstrual blood of the sort you describe very, very rarely, if ever, transmits HIV. When persons with the sort of symptoms you describe have been tested for HIV, less than 1% have HIV, the remainder having mononucleosis and other far more common, community acquired viral illnesses of the sort that most people get from time to time.
Your situation brings to mind another recent post we had that had a happy ending. Here's the link-
http://www.medhelp.org/posts/show/1733048
So, what should be one. Fortunately, the medical care available in Brasil is quite good, Further, because your symptoms could be something like a strep throat that would benefit from treatment, I would suggest seeing a health care professional. At the very least you need a test for strep throat. You may also wish to be an HIV PCR test- if you are experiencing the ARS, it will be positive. I doubt that it will be but it’s clear that you are concerned and I suspect a negative test will provide you with the peace of mind to permit you to enjoy the reminder of your vacation. EWH