My Husband Has Been Battling An Uneasy Stomach For A

My husband has been battling an uneasy stomach for a couple weeks. He hasn't been able to eat much of anything. His balance is not stable. He has diabetes and high blood pressure, but both of those readings are normal. He's been a little dizzy. No fever. Sleeps quite a bit. He did vomit a little last night after eating an ice cream cone. Do you have any idea what this may be?