Wouldn't the acid in the tomatoes make you more nauseaus??? I guess its worth a try if nothing is working.
I've also had many migraines with nausea, and I've noticed that Ginger (little tiny bites at a time) REALLLLLLLLLLLY help the nausea. At least for me..so does chewing mint gum, drinking gingerale (help the nausea), as well as putting pressure on your pressure points on your wrists! For allergy migraines, I think lots of water to flush out what you were allergic to would help, and do some deep slow breathing. Then try to picture blue light surround your headache and soothe it. This usually helps me, it brings me to a point that I get so relaxed that I can fall asleep and wake up with no migraine. Also, if you know someone that does Reiki, ask them to do it on you when you feel sick. My mom does Reiki, and the technique works pretty well at scooping away the pain.
Ok those are my suggessted remedies. I hope you feel much better! Good luck!

Liana