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In case, your test at 8 weeks , is normal (Negative), then it is 90% sure that you do not have HIV infection. Confirmation at the end of 12 weeks, can be done to clearly tell you that you do not have HIV.
HIV symptoms can be very confusing, and many other conditions can be mistaken for HIV.
You should consult with your doctor, who can examine you, and help in proper diagnosis.
In some cases, people with common cold. Sinusitis, bronchitis, have persistent cough and other symptoms, due to persistent inflammation. Stress and anxiety can also be a significant factor.
In such cases taking anti inflammatory medications like Ibuprofen , and antioxidant supplements will help in symptom relief.