Cant eat...cant sleep....and lots of cramping...maybe braxton hicks!!?

ok im 31 weeks prego....for the last 2 weeks i have gone with maybe 3 hours of sleep a night....wich i know whenur this far along it gets hard to sleep...blah blah blah....bu ti have a 2 1/2 year old at home wih me all day....now for the last 3 days i havent been able to eat ANYTHING....not even a small bowl of cereal.....i feel sick after i eat.....i have had really bad cramping...they last about 1-2 mins...then go away...they come and go at diffrerent times...sometimes every half hour sometimes every 2 hours....no bleeding....just not being able to eat and the bad cramping....i never experienced this with my first.....so any answers will help!!!