Use a charger meanwhile, then buy a new battery (most likely the battery you have now is dead).
Oh yeah does it even turn on with the charger? If it doesn't turn on with the charger remove the battery and try again. If it fails again check where the charger connects to the motherboard to see if it's loose check the "battery" light on the laptop. If it's lit up it means it's feeding electricity to the battery but the battery cannot hold a charge and needs to be replaced.
If there is no battery light turning on while plugged to the charger take it to a computer repair shop and ask them to check the DC power jack. It could cost you anywhere from $50-$250 to repair depending on where you go. (geek squad=$250+, local computer shops will probably do it for less)
^ $75-$100 for a craigslist DC jack job=expensive. We charge in Texas (in my business) $75-$100 for the DC Jack repair with 3 months labor warranty, part is 1 year depending on our source no questions asked. Unless we see obvious gravity damage (dropped). An individual maybe can charge $50, I would not dare pay $75 to someone on craigslist unless they have a physical location for their business.. Anyways DC jack repair is pretty easy once your experienced, can take 15-30 minutes.
i was having problems with the battery on my hp laptop too, at about one month of age. sometimes it worked, sometimes it didnt. i emailed hp tech support, and this is what they told me to do. it fixed my problem.
right click on "my copmuter" "computer" depending on os,
go to "batteries"go to "ACPI control method battery" pr similar NOT THE POWER ADAPTER MAKE SURE UR DOING THE BATTERY!!!IMPORTNAnT!!!
right click on it and uninstall it, reboot the coputer...
that helped me...
also, maybe ur laptop came with a battery test utlilty, since mine did
i think you should buy a new one,if the old battery is under warranty,you can contact the seller and exchange a new one,if not,you can search on google or buy on ebay, as i know http://www.laptop-battery-chargers.com is a good shop.you can try it