Might be good to get your records if you can from that dr or whoever has the records now.. If the office totally closed sometimes the affiliated hospital may have the records..
I think with the aging baby boomer generation and the slowed economy - SSDI is having to tighten up the purse strings, you may have slipped through the other times.

If you can't get to the same dr find out who replaced him & has his records now?
Or make appt with another dr, just to have a visit on record for now.