If I don't drink water every hour or so I get really tired and get headaches. Why, and does this have anything to do with metabolism?
Get a blood pressure unit if you don't already have one.They are about 40 to 60 dollars.And check your BP in the morning when you get up and just before bed.BP is a silent killer so keep up with it.
It has everything to do with being hydrated.
You may want to get your kidneys checked. It may be nothing, but then again.
You could be dehydrated or anorexic. Some anorexics have the same issue