I am sorry but I cannot tell you the accuracy of the Tridot test at 4 weeks as it is not a test that is used in British Columbia. It is best to ask where you test to find out the accuracy of the tests they are using.
What I can tell you is that receiving oral sex is not considered a risk for HIV, as the virus is not found in saliva. This is not how we see HIV being passed. The STIs you can get this way are Gonorrhea, Chlamydia, Herpes Simplex Virus, Syphilis, and HPV. You can check out your risks related to receiving oral sex in our Know your chances | SmartSex Resource section.
You can lower your risk of infection from these STIs by using a condom when receiving oral sex.
Let us know if that helps answer your question or if you need more information,
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