For the zucchini hashbrowns to work, you have to really press the moisture out. What I do is lay some paper towls on a bath towl, then place the shredded zucchini on top. I roll it up, then sit on it for a while. Pressing between two large books could also work for the less adventerous
Other ideas for including veggies in breakfast include making the jicima oatmeal. Or using spinach. Today I had scrambled eggs with spinach and salsa for breakfast. Often I will heat up frozen spinach and press out all the excess moisture. Then I'll blend in 1 tbsp mayo or a soft cheese and use that for omlette filling.
AS for the green tea, caffine could be playing a part. It oculd also be mild dehydration. Even though you are drinking alot of water, green tea is a mild duretic and can dehydrate. I drink several hundred oz of water, but on days I donate plasma I can't have coffee or tea in the morning or I'm to dehydrated to maintain stable pressure.
For most of the health benifits of green tea you do need the caffinated kind. You also need massive amounts, much more then 3 cups a day. Using a suppliment is a much easier way to get in the needed amount.
Be careful of other ingredients in teas as well. I can't have any tea with chamomile or I get nasty headaches. If you have any kind of allergies or hay fevor you have to be extra careful about teas. Also watch for senna in some diet teas. This can be a rather harsh laxative.
I enjoy Good Earth Slimming tea. It is a duretic so it can dehydrate you if you're not careful. It has no senna or caffine though and I really enjoy the taste. You can explore a wide variety of teas. Use some DaVincci syrups in them to get even a wider variety of tastes and a sweet treat.