iCloud took over iPad

[QueenMe]

I am dealing with this alert that took over my iPad and I can't get rid of it and it doesn't let me to do anything, even shutting down.
Message:
"iClous Backup
This iPad hasn't been backed up in...weeks. Backups happen when this iPad is plugged in, locked, and connected to WIFI.
I did try hitting OK which doesn't make it to go away even for1 sec. Using iPad even for shutting down is impossible. I connected it to my computer and changed the setting (via itune ) to backup to the computer rather than iCloud. I don't really need to backup anything.
What else shall I do?

[QueenMe]

Update: I could eventually re-start it and it fixed the problem.