If the CEL turned itself off you have nothing to worry about, at least until it comes back on.
I suggest you get another opinion regarding the catalytic converter. Not knowing the exact codes from the computer makes it difficult to make an educated guess, but it's entirely possible that the problem is (or was) something much less expensive than a new cat.
The CEL only comes on when the computer detects something operating outside normal parameters. If the light went off it means everything is now normal. Even if the light comes back on, it does not mean imminent disaster. The light is an early warning system, and it means you should have things checked at your earliest convenience.
There may be nothing wrong with the cat. Maybe an O2 sensor is reaching the end of its life, but there's nothing here to indicate a bad cat except the mechanics opinion, and we don't know what the code(s) indicated.
I suggest you check the fluid levels, make sure the tires are properly inflated (including the spare), and enjoy your holiday trip home. Don't worry about the light unless it comes on, and if it does, have it checked when you reach your destination.