The highest straight you can have is 10-J-Q-K-A and the lowest is A-2-3-4-5. The cut off point if you like is the ace, therefore you can't have straights such as Q-K-A-2-3.
Edit: lol, didn't see UFC's post but that's the idea.
you never quite mentioned what variation of poker you where playing and also what the community cards and your hole cards where, but either way the J,Q,K,A,2 is not a straight in any of the variations of poker I know.