Had protected sex weeks ago. after, cough with mucus, sore throat & loss of voice. coworker in office had same. now runny nose & dry cough. cold/hiv?

Sounds like a cold.: By the description of your symptoms, I would presume that your symptoms would be due to an upper respiratory infection, either viral or bacterial, and would likely have no direct link to the relations you had weeks ago. That being said, if the symptoms have been going on for weeks, then you should see a doctor for an accurate diagnosis.