weird screen respond on lock screen

http://www.use.com/7ccb4310219996db3cdf

after replacing my home button, screen goes crazy some times and shows moving lines. When i press the power button twice it goes back to normal . Also some shadows appeared on the lock screen, around the digits. when I take a screen shot, it is just fine and the photo itself on the phone is fine too. Also the apple logo during boot up is not as sharp as it was.

can you help please