sore throat after waking up

I've been pulling every day for about 2 months, and since starting I notice I nearly always have a mild sore throat when I wake up each day. It disappears as soon as I start to pull. At first I thought it is just a detox symptom, or else that I was fighting off a virus, but after all this time? I should add that the dry air and central heating at this time of year probably play a part, but still... Has anyone else had this happen for such an extended length of time?