Why Isn’t My Charger Working? (long)?

I have a 4th generation iPod Touch, updated to version 5.1.1. I bought a bundle of chargers, with an iPhone charger just so happening to be in there.
There is no problem with it – other than the fact that it sucks.
About 2 days ago, it stopped working. It just didn’t work. I have to hold it in a specific position for it to charge when it dies; and that isn’t even the worst part.
It won’t charge when it restarts. Even if the wire is in the EXACT position it was when it was able to charge.
When it loses all of the battery, it only charges just enough battery to restart. Only like, 10%. Even though it says, “20% battery remaining”, it only dies like 5 minutes later.
Let’s break this down:
20% dies in 5 minutes.
20 divided by 5 is 4.
That means that 4% of battery is supposedly drained every minute.
That’s 1% every 15 seconds!!
That’s insane!!
Why can’t it charge like that?!
Moving on, sometimes, it actually is 20% charged, and lasts me a little longer. I have a special app (called Battery Pro) which tells me how much battery I have and how long it lasts if I do something.
For example:
Listening to music: 6 hours in sleep mode.
Surfing the web: 1 1/2 hours.
What does it really say for surfing the web?
2 hours.
2 hours.
I’m lucky if I can get 2 minutes out of this battery, but 2 HOURS?!?! REALLY?! At 20%?
Well, I know what you’re thinking:
“Why can’t you just get another charger?”
Well, first off, I know. It’s cliche.
Second, I got in a car accident on Tuesday. I don’t have a car. And the nearest Walmart (or any places that sell phone accessories) are miles away. I can’t walk there, (obviously) and I can’t afford to get a taxi to go ALL the way out of town for a lousy charger.
So that only leaves one option: the Internet. More specifically, eBay. It’s cliche, too.
I’m lucky enough if the battery can stay long enough for me to find and purchase one.
Will that even work?
Why isn’t it working? Is it my iPod, or just the charger itself?