I had a HIV RNA PCR and 4th generation test at 26 days post exposure. Results were negative, I have symptoms, how accurate are these results? Worried

Accurate but... While the tests you have taken are good, the are not fool-proof. The standard is to retest at 6 months. This gives your body time to form antibodies. Be careful.
You could get a . Retest, if exposed to the virus 4 weeks earlier it should be detectable. If you have symptoms, the viral load goes up then down meaning an immediate viremia. Get a standard HIV screen if it saves money, get retested for piece of mind. You have likely been terribly worried so any type of viral illness if going to be interpreted as HIV viremia. Good luck man, i think your ok, retest ease min.