It should not be possible to damage the sound drivers by just having the volume maxed out. It's not like owning a component sound system, with amps or drivers more powerful than the next stage, so you can blow them. The iPad's drivers will be designed to work with whatever the iPad's volume can be set too.
From the sounds of things, you 'might' have damaged the headphone jack when you yanked things. Not knowing exactly what got yanked or how hard, I've no idea if this likely.
In the mean time, try the usual fixes below, to see if they help. If not, it may indeed be hardware. If you have an Apple Store nearby you could make a Genius appointment and have them look at it. Actual repairs (if necessary) will depend on whether the iPad is still under warranty, and whether you purchased AppleCare.
As for you ears, go to Settings > Music > Volume Limit. You can set a Maximum Volume for your headphones. I'm not sure if it works with anything outside the Music app. Other music apps may have a similar setting.
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The Usual Fixes
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When you have problems with an app it's a good idea to clear it from RAM.
Close/Clear the app:
iOS 6: With the problem app closed, double tap on the Home button to get the multitask bar. Tap and hold on any icon in the bar until they jiggle, then tap the minus sign on the problem app.
iOS 7: Double tap the Home button to get the multitasking display. Swipe up on the problem app's thumbnail image (not the icon).
If that does not work try a restart,
Restart: Hold down the power button until the power off slider appears. Slide it off. When the iPad finishes shutting down, hold down the power button again until the Apple logo appears. Apple recommends you restart the iPad at least once a month.
and then a reset if that does not work.
Reset: Hold down the power and home buttons until the Apple logo appears. The iPad will reboot. This usually takes a bit longer than a restart.
Reset All Settings: Another, somewhat more drastic thing you can do is Reset All Settings. You'll find this under Settings > General > Reset > Reset All Settings. It won't erase any of your content, apps, or accounts; but you will have to go through most of your other settings and re-tweak them back to your liking.