Hi Thailand and Tourism,

For any of you guys with experience, I was wondering if spending $5,000 Canadian to Thailand for 2 weeks from Dec 15-31 is worth it?
I've never been to Asia and I had been watching Thailand tourism videos which inspired me to visit. Unfortunately I am seeing flight prices from Toronto to Thailand being $3,500 CAD round trip accommodations tours, I'm assuming I'd be spending $5,000 CAD during the late December period. 5K is a significant amount of money for me, so I was wondering if I am getting good value for the 2 week period.
My rough itinerary is to fly from Toronto to BKK, spend 3-4 days in BKK, then fly to Ao Nang, Kalbi. I will spend the rest of the trip around, using Ao Nang as my main base, visiting nearby beaches and islands such as Phi Phi island and Phuket as I want to enjoy a lot of nature and beaches as the focus for this trip. Is 5k reasonable for my Thai experience?

Edit: Just to clearify, my flight itself is going to cost $3,500 CAD, which is the most expensive issue.