Plugged in, Not charging. Dell L502x, what is wrong?!

OK, so I've owned my Dell XPS 15 L502x for just over a year (thus, I am out of my warranty period) and recently it has stopped being able to charge. I am completely tethered to the AC power adapter to use it as I'm on 0% battery and have an inability to charge it. I am on windows 7.

As well as my inability to charge the laptop, I have noticed the following things:

The computer states that 'No battery is detected' when the battery is inserted, when I hover over the battery icon in the task bar.

4 orange and 1 white lights are flashing on the battery indicator above my charging port and above my keyboard, when the charger is plugged in.

Furthermore, a couple of days ago my computer completely failed to boot and I discovered that my 500GB hard drive had crashed. Thankfully I managed to get all my stuff back, but I now need to get a replacement hard drive. I am currently using an old 150GB one that we had in the house.

I have looked all over the net for fixes and have tried many for example updating BIOS, uninstalling the Microsoft ACPI compliant control method. But all so far have been unsuccessful.

From my memory, Within my BIOS settings it says something along the lines of AC Adapter = Uknown. I will find out for sure and update this.

I would also get this message:

But mine would say 130w apposed to this one's 65.
But then I look at my original charger and it is 90w?!  
Also, the transformer of my charger makes a nasty noise. That noise as if you haven't got a plug pushed all the way into it's socket and it's like an electrical flicker! (I hope you can understand that).


Basically, what is bothering me, is what the actual source of the problem is. Is it the battery? Is it the Charger? Or is it even the motherboard?
I would happily replace the battery and charger, IF I KNEW that this was what was causing me laptop to act like this. Else, I don't want to waste money, that could go on a new laptop.  

What is wrong with my laptop, and what is it trying to tell me with these messages?
Is the problem with my hard drive linked to the problems I detailed above?

Thanks to all in advance!

Morgan