HIV from drug use straw ?

Hi, welcome to the ehealth forum and I am glad to help you.
You seem concerned by the belief that you are HIV positive because of typical symptoms of acute HIV infection despite the test being negative at 6 months after exposure which you think is negative because you are a late seroconverter due to Hep C co-infection.
Few instances of late seroconversion because of HCV co-infection have been reported in health care workers in which the health-care workers tested negative for HIV antibodies greater than 6 months postexposure but were seropositive within 12 months after the exposure. But in your case the test for HCV is negative even at 6 months post exposure. The other possibility for delayed seroconversion can be antiretroviral therapy after exposure as the same can delay seroconversion. About 25% of those with HIV/AIDS also have an HCV co-infection, and their liver disease is likely to progress at an accelerated rate. You should consider alternative diagnosis with your physician for the physical symptoms that you are experiencing as the false negative test is very rare but still you can keep the option to be retested at 12 months as discussed above.
Hope this helps. Take care.
Note: This answer is not intended as and does not substitute for medical advice - the information presented is for patient education only. Please see your personal physician for further evaluation of your individual case.