in theory, natural skin concoms might allow small amounts of virus to leak through. However, in the entire 30 year history of the known worldwide
epidemic, there have been no reported cases of HIV that occurred through an intact natural skin condom.
2) No, HIV doesn't cause such symptoms. There might be nausea, vomiting, or diarrhea in ARS, but never as the only symptoms. And as noted above, the symptoms started too soon.
3) Your risk is zero or close to it.