I can only comment on the HIV tests that we use in Canada.
The 3rd generation HIV antibody test we use is 95% accurate by 6 weeks and would give you a final result by 12 weeks. If you had this test in Canada at 12 weeks we would tell you that there would be no need for any further testing.
The best person to ask would be the person who did the HIV test for you, they would let you know how accurate your test is at 12 weeks.
It can be common for people to worry even when the result is negative. If you find that you are still worried after getting this information, I would suggest having a look at our worry page, it has some helpful tips.
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