xenius 42inch problem :(?

hi can someone help please. well ive a 42inch xenius and sky man came to install sky earlier pulled the one side of my tv off the wall looking for the hdi socket suddenly about 4to5inches wide on the right from top to bottom its flashing allsorts or colors at diffrent speeds sumtimes stops but leaves a solid line then starts flashing and so on. any help will be awsome specially with the new mw3 out soon it will be killing me lol cheers :)