What Causes Fatigue With Sweating And Dry Heaving?

My husband, 48 years old, runs 4-6 times a week, eats healthy had malignant melanoma removed three years ago.....it hadn t spread. They mentioned doing a chest xray but never did one. Nothing else was done. He goes in twice a year for derm. checks. The past 2 weeks he s been very fatigued and going to bed very early. Not stressed! This morning he woke feeling dizzy, sweating and dry heaving. He couldn t stand up. The only thing that sorta worked was laying on his stomach. He thinks veritgo, which runs in his family, but I m wondering if it could be a reccourance of melanoma.... Thank you