What Causes Loss Of Appetite And Heart Burn With Erectile Dysfunction?

Hi! My husband and I just went on a cruise during which he started to feel unwell. At first we thought it was sea sickness but we have been home for five days now and the symptoms persist. Mostly he is tired, he has very little appetite, heartburn and he feels over heated frequently and most disturbingly he is having difficulty for the first time in his life maintaining an erection. He had a routine checkup before before the cruise and a full panel of blood work and it all came out fine.