A good fast is often accompanied by some type of goal related to establishing a healthy diet after the fast, and re-entering with solid foods. Have you established this?

Yes, you will lose weight but how will you eat afterwards? And what activities will you participate in during? It's best to take it easy.

okay yep
i will probably go for a run 4 days a week

Aerobic effort may cause light headedness during a fast, but each person is different. I'd suggest gentle stretching and relaxation or slow walks...but running seems like an overload.

What diet changes have you committed to?