to double check your understanding, if you enter before the expiration date, you get 60 days, not 6 months. After that, you wouldn’t be able to use again, because you can only use it to enter before expiration date
The Thai Ministry or Foreign Affairs issued today a travel advisory for all Thai nationals. They should only travel to Thailand if absolutely necessary. This may mean that the embassy has a reduction in staff and/or consular services (who also issue visas) might be focusing more on affairs related to Thai nationals in Cambodia.
You entered “visa exempt”. Visa on arrival is a different thing. There is a kiosk with chairs for waiting before the immigration line at the airport. This is for nationalities that are not allowed to enter visa exempt. The visa on arrival gives those nationalities 15 days