Welcome to the forum and thanks for your question.
I understand your concern; it's undoubtedly alarming to learn that a recent sex partner has HIV. Still, you are overracting. I would advise you to skip the tests you are planning at 3 weeks. The RNA test is very expensive and really won't help resolve your fears; even if negative; you will still need to wait for later testing to be sure you weren't infected.
Instead, I recommend a duo test at 2 weeks. If the result is negative, which it probably will be, it will be 80-90% reliable -- not quite as good as a negative RNA test, but very reliable and much less expensive. Then you can have another duo test at 4 weeks, which will be definitive. The 8 week test really won't be necessary. There's a lot of misunderstanding about the time for reliable testing. All the debate about 3 months versus earlier testing is relevant only if antibody testing is all that is done. With the combination of p24 antigen plus antibody, 4 weeks is definitive. For more discussion of this, see the thread linked below:
As for HIV-2, you needn't worry. If your partner is not an immigrant from east-central Africa (Cameroon, for example), the chance she has HIV-2, and not HIV-1, is close to zero. Why not just ask her which virus she has; almost certainly it's HIV-1.
Finally, remember the average risk of HIV transmission by vaginal sex, if the woman is infected: about once for every 2,000 exposures. (That's why many male spouses of HIV infected women never catch it, even after years of unprotected sex.)
So don't panic; almost certainly you're fine. Feel free to return with follow-up comments to let me know your test results. But in the 9 years since this forum started, there hasn't been a single case of new HIV from someone who posted a question about their risk. You aren't going to be the first.
Best wishes-- HHH, MD