I'm 8 Weeks Pregnant And Symptoms Of Hyperemeses Have Started.

I'm 8 weeks pregnant and symptoms of hyperemeses have started. I experienced this with my first pregnancy 5 years ago. I am trying to avoid having to stop working like I did before but so far none of the suggested remedies are working. I've tried ginger, lemons, crackers, bread/toast. So far tge only thing I can keep down is plain cooked egg noodles. I don't want to take Zofran like before, what else can I do? What causes this to happen ?