Acer aspire 5610, wont start

Question

HelloI have had this model for 18 months. Just last night I turned it on to find thebattery was run down so it went into hibernation. I plugged it into the power (same sourced used since I got it - light on battery shows it's working) and something has obviously gone wrong as it will not work at all. Not fan, no lights, dead to the world! I need may laptop back!! Any ideas? does the main computer battery need changing perhaps? never had this before.Thanks, Anna