Hello Welcome in H.C.M. I have gone through your query regarding severe pain secondary to gingivitis, lump under the tongue and back of throat. Here I would like to tell you that any pathology in the above area may give rise to reffered pain in ear due to same nerve supply. Such situation is named as referred otalgia. To find out the nature of lesion in oral cavity you are advice to do these investigations- 1- Culture and sensitivity of saliva. 2- VDRL. 3- Blood- CBC, ESR, Blood sugar (Fasting and post parendial) Beside above investigations a thorough examination of your mouth and oral cavity along with examination of ear is necessary to make a diagnosis that may be accordingly manage. Regards.