Welcome to the forum. Bottom line: You do not have HIV. All is well.
Your exposure was low risk; my understanding is that heterosexually transmitted HIV remains rare in Sweden (and throughout Scandinavia) except in certain population groups; recent African immigrants are an obvious example. No matter how many partners she has had, it is unlikely your partner had HIV.
Your symptoms don't sound typical for HIV -- just a cold or other minor respiratory virus. Almost everyone with new HIV has a substantial fever; and 70% have sore throat, and skin rash, and fever (i.e. all three). Coated tongue goes along with hundreds of medical conditions, including the common cold.
But most important, HIV test results always overrule symptoms and exposure history, as long as enough time has passed since exposure. For the duo test, that time is 4 weeks. Your negative result at 25 days was almost 100% reliable, and the 36 day result proves it. Even if your exposure were truly high risk and even if your symptoms were typical, you can rely on the test results.
In contrast to the brief message you had on the community forum, you don't need to wait 3 months for definitive testing. That advice applies to the antibody-only tests, not the duo test (and even for antibody-only 6-8 weeks generally is sufficient).
So all is well. You don't have HIV and do not need any more testing. If you have a regular sex partner, you can continue unprotected sex with that person without fear of transmitting HIV.
I hope this helps. Best wishes-- HHH, MD
Thank you very much for the advice! A real relief that is!
All the best wishes!