When I get up I get lite headed but I start blacking out and mybbody starts to shake. I drink plenty of water. This has never happened before.

May be. A number of things but if only related to standing up and no vertigo ensues then you should be seen by your doctor. If you feel like you are off balance until you hold still then probably just benign positional vertigo but it is impossible to tell you with any certainty. Best to see your doctor.
Abnormal! Dehydration, anemia, bleeding, are causes of postural hypotension as you describe. Serious potentials, be checked.