Ben Wa Balls

I recently bought the Ben Wa Jiggle Balls and used them for the first time.

Am I right that your body does just naturally clench aroudn them and you don't have to do any exercises yourself when using them?

Also, when I used them I kept feelign the urge to pee and had to keep running to the loo but I didnt actually need to do anything. Is this just the feeling you have when your pelvic floor muscles are beign worked?

Thanks!