I think i'm starting my period. but the blood is watery. i've been nauseated the past week and the past couple days my uterus has hurt?

Abnormal Period: Without further information, it is hard to say. Of course, it is possible you are pregnant, and a home pregancy test - test twice, a week apart - would address that possibilty. You could also have a uterine polyp, or a vaginal infection. Regardless of the result of the pregnancy test, you should probably contact your gynecologist to discuss these "new" menstrual features for you.