Hey, you can go to Bangkok, and 2 days are okay. I just went there 2 weeks ago and left on Friday night and back on Sunday night. You can visit museums, spend some time at go-go boy shows, try on the local food, and even enjoy wide ranges of spas and massages.
The price depends on the hotel and the flight. $3000 is more than enough, including the flight ticket, hotel, taxi, food, and souvenirs.
P.S. Remember to bargain for a lower price!!!!!!!!!!!!!!!!!