Started a cold 10 days ago. bad sore throat progressed to lots of mucous. now mucous is all gone but sore throat is back. could it be a new virus?

Maybe. Maybe not.: Throat pain can be from strep throat infection (antibiotics are needed), a cold or influenza (antibiotics usually not used), or from some other cause such as allergies or irritants. Usually, a person sees a doctor if the sore throat is bothersome, recurrent, or doesn't go away quickly (mainly to see about antibiotics). Some lozenges or Tylenol (acetaminophen) can temporarily decrease throat pain.