To be safe book your flight out of Thailand to Vietnam or Cambodia before your 60 day visa runs out. Maybe you will find a changeable flight. The low cost airlines, probably not, but their fares are very reasonable. Like 50 USD one way. Many will say they are never asked about this flight out of Thailand. I've been asked to provide proof of a flight out a couple of times, usually by airline personnel.
I speak some Thai, however I find it totally unnecessary to fluently speak Thai to function in Bangkok and the other major international and tourist areas. I spend very little time in small villages and farm areas. The bottom line, it's just not necessary in my day to day life in Thailand, to be fluent in Thai. As to Americans who get mad at people for speaking Spanish, or an Asian language in the USA, it's just a cover for their racism and bigotry. Note, I've never seen an American getting mad at someone for speaking French, Italian, German, Swedish... In fact they will compliment Europeans for speaking these non-English languages. Ex: It sounds so sexy or intelligent.
Lastly, people always reference language as an issue. In my 10 years experience in Thailand, English is never an issue in primary tourist and international locations. Only when visiting small villages are small local beach towns, is language a minor issue.
I've lived and visited both. In short in Thailand you get better infrastructure, housing, food, medical; for a fraction of the costs in the Philippines. Also, as someone else mentioned, weather, the Philippines is directly hit by several typhoons every single year. Thailand typhoons are not a major concern. Crime in the Philippines is significantly higher than Thailand. Lastly, compare Bangkok to Manila. No comparison Bangkok is a far better city. Yes, Philippines have some great islands and beaches to visit and vacation on, but the main population areas have many issues.