Welcome in H.C.M.
I have gone through your query regarding sore throat
and swelling at back of tongue.
It appears as your back of tongue is having some pathological lesion which is giving you feeling of rubbing in throat. The possibilities are-
1- GERD & LPR.
2- Hypertrophied lymphoid follicles of base of tongue.
3- Chronic glossitis
of base of tongue.
To confirm it your pharynx should be thoroughly examine by an ENT specialist
Till your appointment is fix and in waiting period you may do-
a- Warm saline gargling.
b- Take antacids.
c- Avoid spicy foods.
I hope your query is answered and sooner recovery is expected.