Screen presses other buttons

Hello everyone,

My screen got cracked and I replaced it back then (never knew how to do it) since then when I press the letter 'K' it says I hit the letter 'O' and when I press '<' (so backspace) it says I hit the letter 'M'.

This happend a month after the first replacement. So meanwhile, I started doing repairs myself so I replaced my screen again. But that didn't work.. it still finds the wrong buttons to press :S what's wrong with it?

Regards,