I'm dizzy and lightheaded. Is my blood sugar low?

I have been a vegetarian for almost a yr., but recently cut out milk and egg products as well. Today I'm so dizzy and lightheaded, I feel as though I may actually fall down when I stand up. I just ate some pumpkin/squash ravioli and drank water, (16oz) so I know I'm not hungry or de-hydrated. But this dizzy stuff is scary! I work 3rd shift and I'm completly alone at work! HELP!