I feel nauseated when i wake up too early . i feel a little better after drinking water. i am not pregnant nor do i have any health issues.

Many causes: If not pregnant, you could have hypoglycemia, poor gut motility so your stomach acids build up until you drink water which raises your ph. Other less likely causes are alcohol withdrawal, chronic obstructive lung disease, uremic syndrome, psychogenic nausea, and even high pressure in your skull/brain. You need to see your doc if you've had it a long time to rule these and other causes out.

Circadian rhythms : When you wake before your body expects it, the hormones and body chemicals (e.g., cortisol) that help you rise and be ready for the day probably haven't been activated. As a result your sympathetic nervous system (fight or flight) responses jump to action to be ready. If this happens a lot or even when wake on your typical sleep cycle check in with your primary care doc to see what's going on.