I've done that twice, both times the TV returned to normal after a couple of hours.

 

I bought a professional degausser for this sort of thing..it was liek 30 bucks US so I figured what the heck..you can also use a corded drill and play it next to the TV and pull the trigger for short bursts..this will pull some of the gauss out of the tube..also you can use a smaller magnet and try to massage the gauss out of the tube..your TV should get rid of it though..every time you turn the TV on it degausses itself a little bit..the degausser is a wonderfull thing though..highly recommended..