A sudden drop in blood sugar would give other signs....as well.
Sweating, muscle twitches, some nervous anxiety, shaking are
typical.

I was having a type of episode with my ACE inhibitor crisis.
I'd get a strange feeling and need to sit down, and when I changed position I'd almost pass out. This would come after walking or shopping. I haven't had one since I was taken off that drug... but lisinopril increasing bradykinin, was dilating major vessels too fast, and that was what was happening to me. I did not however have any DejaVu.

Children do get abdominal seizures.(it is considered rare, however).
This article says abdominal seizures are connected to temporal lope epilepsy....and temporal seizures begin often with DejaVu.
I think you need to have this explored further with a specialist.