1 cup of mocha is fine. dont't worry. I really dont't think all these symptoms are because of the mocha. 1 cup of caffeine a day is still considered okay. Although you should try to cut-back, if you're a tea/coffee drinker.
I didn't really experience mild cramping when i was pregnant, but i'm sure you're well taken care of by your gynae.
The constant need to pee is very normal. I remember waking up many many times at night to pee.
22 weeks...you're more than halfway through! Haha. Good luck!