[...stuff...]
(sorry about the long blurble) please help me!! It feels like quite a big moral question to me...
The moral way is to get back to the dojo and practice. Even if the shinpan made a mistake (which you say you didn't realize until after reviewing your own video), there's no point in giving it any further consideration. Any objection made at this point is either, whining, or telling a shinpan how to do his job. Neither position is admirable.