Sounds as if the best/first thing you should try is a reboot of your iPad:
Hold both the sleep and home buttons until the screen goes black and then the white Apple logo appears (the slide to lock screen may or may not appear). Then, once the logo appears, release the buttons. After a time, your homescreen will appear.
Note that it may take some time to see the logo or to get the homescreen back (or both). Have patience, it will happen...
This reboot is sursurprisingly effective at fixing a vast number of iPad "troubles." Give it a try and let us know if it works.
Marilyn