The clicking is your solenoid switching, but sounds like there isn't enough power coming from you battery.
This could either be the battery at fault or the charging system (alternator/Belt) ar fault.
Only other think I can think of is if your starter motor is jammed, though this is unlikely.
Get someone to try to turn it over with the lights on. If you can hardly see the lights when trying to turn it over then it's the battery.