I would also skip the oral surgeon and get in to see an ENT right away. You need a tongue specialist now, not a tooth specialist...I would vote for this being a case of thrush....and a pretty severe one at that.
Hope you get some answers...and some relief soon.

DX 12/6/10 of T3 SCC Tongue.
Surgery 1/3/11 was hemigloss & forearm free flap, midline mandibulectomy, Neck Disection-All nodes clear.
Ended rads 5/11/11. Taste buds back to about 80%. PEG removed 4/5/12, experimenting eating real food again. If I can do this, so can you !! Stay Strong.