Vixmom: That's happened to me a couple of times, whereupon I learned that an iPad or iPhone can get stalled out or locked up just like anything else. To fix it, you have to force it to shut down and reboot itself which will restore its functionality and settings.
Press and hold the power button, and while that's being held, press and hold the home button ... until it shuts down and you see the apple logo indicating it's restarting. Once it's back up, should be good to go. If not, it would then be time to stop in at an Apple store to have them look at it.
Not charging is one symptom that it's crashed. Another is if it just goes dark while you're using it and it won't start back up. Same remedy applies.