What is this displayed lines on top of my android home screen?

im using a samsung galaxy 5. after charging i saw a displayed line on d home screen almost on top. but when i key in my security pattern it also disappeard. plus the emergency call doesnt work, screen blaks out and i have 2 do it again to get to that screen. its so annoying. pls help. that screen. its so annoying. pls help.