I am also pregnant with #4. Had day sickness as well up until going into the 4th month but am fine now...hopefully time will heal that. Not sure why you have the awful taste. Ginger is a natural remendy for stomach upset, to me it tastes awful but it works a little too.
As far as the kids, I have a 7, 5 ,and 2 1/2. They can be crazy too but at the same time they are kids and have so much energy. Now we bought a couch specifically good for jumping cause I knew it was going to happen and well I don't want to say no all the darn time. But we've taught them not to do it at other houses. Maybe get them a small trampoline to put outside to get their jumping urge out. Send them outside to play or if you can't set up projects for them..painting, or somersault races or something. They just need to be active and re-directed. It's hard to have patience especially when you feel horrible. But if you get some projects ready for them for these kinds of times, you'll be relieved.