Whenever you want to change your visa category or extension or long stay or marriage or employment, easiest thing for western people is to go neighbour countries and apply new visa with proper list of documentation with new category rather than staying in Thailand doing drama with all the immigration officers of Thailand.Sometimes you have to pay extra money for special services you know 😁
If your english is good then you can work as English teacher in Thailand. Try to contact local schools. Its little bit easy for you as Philippines citizen.
if your visa is not multiple entry visa then you have to inform immigration for re-entry. 1000 baht for visa single entry and 3800 baht for multiple retirement visa . Please check your visa it’s multiple or single entry.
THB (once in a month ) 2 photos and supportive documents and 1000 Thai baht. If you cant find anything, Just go to embassy, outside embassy you will find many agents who will book appointment for you for next day