I Have Had A Stomach Ached For Over A Week.

I have had a stomach ached for over a week. No vomiting, no diarrhea, just feel nauseous
and I kind of taste a metallic. I have been taking a magnesium tablet so I quit taking last week, thinking that could be causing the nausea. Saturday I was actually sick and vomited repeatedly. Last session 8pm Saturday night. Yesterday felt puny but no vomiting, ate bland food. Today nausea returns, metal taste but no vomiting