I had the same experience. I think the Americans reject everyone the first time. I do not know why. As an aside Never tell them you are visiting someone. "I want to see the Grand Canyon and Niagra Falls." If you have a friend you have a place to live.
Travelocity is a good source but I book the ticket through the airlines direct. If anything goes wrong it’s impossible to rebook with Travelocity. You might want to consider the bus from BKK to Pattaya. The flight is 20 mins and not worth the money.