Oral sex is low risk to start, even with an HIV infected partner. Your symptoms don't particularly suggest HIV, which doesn't typically cause cough and rarely causes congestion, stuffy nose, or sinus problems. In any case, your negative HIV test at 7 weeks proves unequivocally your symptoms were not due to HIV. You really didn't need the 3 month test, but you can count on a negative reslt. I have no opinion about other possible causes for your continuing symptoms, and agree with your plan to see a provider if they concern you.
Good luck-- HHH, MD