no worries, just go to the airport for your departure and pay 500each day of ovetstay...if you have overstayed over 20days...dont worry only just pay...do not go to the immigration dept. Just depart at the airport all can be done.
this is the kind of madness and double standards if the thai immigration...they love to see you sweat and confuse...so you tell me this is kind of treatment we want.