Ditto on sciatica, especially with #3. Thank God for the chiropractor.
Cravings: milkshakes. Not ice cream, not milk with anything else, but milkshakes. And with numbers 2 and 3, salty things.
I usually don't eat a lot of salty stuff, and I don't add salt to things when I cook. But my blood pressure drops when I'm pregnant, and that seems to be what triggers MAJOR salt cravings. Pickles, pretzels, popcorn, potato chips -- I didn't care much, as long as it was salty.