No, you probably do have a leak, the proper test for which requires use of an ultraviolet dye, I believe, which allows for the site of the leak to be pinpointed. Might also be the compressor, but as you say everything else kicks in, then that's probably okay. I think a recharge may be on the order of $100, which you may have to do every year or so, depending upon the severity of the leak, to retain a/c, if you don't want to go to all the trouble and expense of a permanent fix.