Hi there,
It sounds as if you might have dislodged something whilst in transit.
Can you hear any noise when swtitching on the tv such as a slight crackle. Once the tv is on can you feel any static on the screen ( use the back of your hand close to but not touching it the static will cause the hairs to stand on end). This will determine if the tube base has become dislodged.
Beyond this you will need to take the back off it, beware ther are high voltages inside colour tvs so take care with the next bit . Unplug tv from the mains first and undo all the scews holding the back on. Have a good look inside and see if any plugs have come loose push any that look suspect in fully . The tube base is the board on the very back of the CRT, check this is pushed onto the tube fully. Let us know how you get on.