Yeah something is wrong w/ it and it can be a bunch of reasons why. I know on my '93 Cam when my A/C did that it was because my system had in too much freon and it also needed to be vacuumed out. Probably not the same thing for you though. DO a search on here and you'll find alot of info on what it could be, that's what I did when mine was giving me trouble.
It could be anything from the switch itself to low/high pressure in system, bad clutch, and a number of other things.
Probably need to take it somewhere to have it checked out. IF it was stolen is there any chance insurance, if you have compehensive coverage, would pay for repairs that might have been caused by the theft.