I'm expecting my second baby boy any day now. This pregnancy was WAY different from my first. I was less sick this time and sick at different times. My food cravings were less and I had different food preferences. I haven't had any Braxton-Hicks contractions, like the with the first, but did/do have mild cramping after 38 weeks. The cramping in the beginning is probably your body making room. I think I had the feeling like I was going to menstruate but then never did, obviously.
Side note: you may be more tired this time b/c you're keeping up with a 2 y.o. Take it easy when you can, nap and sleep often, and remind your hubby to rub your back and feet occasionally. The pampering tends to be neglected the second time around. I hope you enjoy your pregnancy!
S. - who also has a 2-1/2 y.o. boy