Ghost clicking, lines on screen, screen flickers.

My phones screen ' ghost clicks, sometimes has lines across it and sometimes flicks/scrolls between pages/screens. It's never been dropped or had the screen cracked or broken, it's never been opened and apart from the odd scratch on the back I though it was in good condition. I've had it for approx 13 months (just long enough to be out of warranty) and now I have this ghost character clicking, lines across the screen and random flicking. I've read through pages of help, but everyone seems to get this problem after the phones been opened for one thing or another. I've read that placing a piece of paper in the back to prevent some parts touching, seems to help some. Has anyone had the same problem with a phone that's not been opened for repairs, has no damage externally or been dropped, and did the paper/insulation thing work.

Apple won't help, (out of warren ty period) My service provider won't help either.

Any help? Cheers.