What do you mean by nausea coming from your neck?
Is your nausea coming from your stomach? I know I have similar symptoms as you but sometimes different problems with y body bring on the nausea. I'n my case most of my nausea comes from an unknown stomach problem of mine but other times it comes from my neck, because my neck is so ou of wack. Try to establish what exactly is causing your nausea (where it's coming from) and go from their with a doctor
Welcome to the gastroenterology community! If you are female, could you be pregnant? Have you had any changes in your stools?