Go to the immigration office in the area where you stay TOMORROW,
Pay the overstay fines at 500baht a day (so tomorrow if you're 6 days over that's 3k baht)
then
apply for the 30 day extension for 1900baht.
They'll start the extension the date your current stamp ran out,
BUT
you'll be 'legal' and able to stay on that extension until you're leaving
Just so you know
@Avraham ******
, I messaged you several times about this today and you never checked your message requests. 😕