Headache & Stomach Ache

Hi again! I will probably be posting on here several times a day as it has helped me out a lot today. I am starting to get a nawing headache and my stomach hurts a little bit. This is my first juice fast and I was going to wait another 30 minutes to drink my drink my "juice dinner" and I was wondering about how long the headache and stomach ache normally last? So far, I have had 6 8 oz. glasses of water, one 8 oz. glass of orange juice, and 3 8 oz. glasses of the powdered crystal light.

I am determinded to not give up and do at least a week to start with.