A sore throat is the way that the throat responds to some sort of injury, illness, or other attack that affects the tissues in the throat. Obvious illnesses, such as strep throat, can cause painful sore throats that need to be treated, but these are most often not the cause. You don't mention whether or not the urgent care physician did a strep throat test in the office, but your symptoms don't sound typical of strep (which is more painful than the simple dryness you are describing). Allergies could be the cause as well, as constant post-nasal drip can affect the tissues at the back of the throat and make them very inflamed, causing that dry sensation. Another possibility would be heartburn, or GERD, which occurs when stomach acid passes back up your esophagus. The dry weather of winter does not help, either. Unfortunately, without more information, likely including a physical exam and your past medical history, it is impossible to narrow in on what is affecting you. Please see either your primary care doctor
or an ear-nose-and throat surgeon
) for more help.