Welcome to the forum.
You have carefully researched the situation (thank you!) and I agree with most of your self-analysis. However, I think you misunderstood something you read about ARS symptoms, or perhaps found a somewhat inaccurate website. While peripheral neuropathy may accompany ARS, I'm not aware of it and am skeptical. In any case, I cannot imagine that peripheral neuropathy would ever be the only manifestation of ARS. If it occurs at all, I would expect it to be part of a syndrome dominated by sore throat, fever, and probably lymphadenopathy (lymph node inflammation/enlargement) and skin rash.
In any case, I'm not convinced you have peripheral neuropathy anyway. PN symptoms are generally localized, e.g. in a single leg or perhaps both legs, or an arm, or whatever -- but consistent for that area and not migrating around the body. Your symptoms are more suggestive of the physical manifestations of anxiety, which can magnify normal body sensations that otherwise would be ignored or not even noticed.
Equally important, you are exactly correct about the safety of the sexual exposure described. I cannot imagine you caught HIV -- for all the reasons you state very clearly.
Therefore, as you have perhaps predicted, from a strictly medical or risk perspective, I don't really recommend HIV testing at all -- i.e. reassurance is the main reason to consider it. In any case, you correctly understand the performance of duo/combo testing at 4 weeks, which apparently is only a few days away. So I recommend you do it. In the meantime, stay relaxed. You definitely can expect a negative result.
I hope this has helped. Happy new year-- HHH, MD
Thank you Dr. for the assessment and insight, helps alot. Will try to relax myself.
A Happy New Year to you too!