I realized that there's a national holiday on the 23rd. If I take one more day of nenkyuu, I can have two extra days! The Monday after I come home is also a holiday so I could extend my trip for two extra days at the end too.

I went over to JTB to see if I could change my flight so I could be in Thailand for longer, but I'd have to pay a cancellation fee of 13000 and then rebook the flight. So that turned out to be a no go. I'm not sure if I'll take the 23rd off but I can stay in Kansai for a few days after I come back to Japan.

=/ I should have checked my work schedule before I went to JTB.