Hmmmm . . . well, it sounds like you already know where you made some mistakes, but you fail to give a lot of important details, such as:
- Was this a limit or no-limit game and what were the limits?
- Was this pot raised pre-flop?
- How many players saw the flop?
- Did you have a pair to go with your flush draw?
- In what position was your main opponent sitting? (this would likely affect what sort of starting hand he plays)
In regards to your comment that chasing a flush draw is "a bad idea", that's not necessarily true; what you need to think about when you consider going after a draw like this are mainly two things:
1. Am I getting correct odds
to call the flop/turn in hopes of catching my draw? In this situation you would have needed at least 3.5-1 on the flop and 7-1 on the turn, and although you don't give enough details it kinda sounds like you probably weren't getting those odds.
2. If I DO make my hand, how likely is it that I'll still be beaten? This is probably the more important point in this case . . . even with one of the two club overs on the board, you still couldn't be sure that the other guy didn't have the Kc, which almost certainly made your calls unprofitable. (Note: even if you HAD won this particular hand, making these three calls in this situation would STILL be unprofitable in the long run.)
Hope this helps a little . . . good luck at the tables! (By the way, I don't need the answers to all the questions above -- I just wanted to point out some of the things you should have been thinking about in this situation for future reference.)