It is great that you used protection as condoms work really well in preventing HIV.
There are no symptoms that are caused by just having HIV. The symptoms people get with a HIV seroconversion illness are common symptoms that can be caused by many different conditions, for example the common cold. Just treat the symptoms as a reminder, you are concerned about what happened and it would be good to go for a HIV test.
The HIV tests we use in BC Canada would be very accurate at 8 weeks; we find they are 95% accurate at 6 weeks but that it can take up to 3 months to get a final result.
You probably have nothing to worry about given that you used protection and had a negative HIV test at 8 weeks but I find if someone is really worried about what happened having closure by getting a negative HIV test at 3 months can bring good peace of mind.
We also recommend a final syphilis blood test at 3 months so you could get a blood test for HIV at the same time.
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