something wrong with my keyboard

could someone tell me what axactly is wrong with my keyboard,if im typing and i want to go down to the next line(you press the upside down L shaped button with the arrow on it)Now when i press it it goes to the previous web page ive visited this has never happened to me before

just make sure you have pressed the chat box part.(were you enter the text)
Do you mean the enter button? cause its only the backspace button which should put you back a web page.