You need to make sure that you don't have candida, because switching to a higher carb diet could really set that off.

Don't combine fruits with your other foods. Eat them on an empty stomach.

Make sure you are getting enough fat in your diet! The good fats - extra virgin olive oil drizzled on the rice and beans, extra virgin coconut oil, you might want to supplement with fish oils or some such, as well. Sorta depends on "why" you are a vegetarian, but the good news is that clarified animal fats don't contain all the bad effects of meat.
Fat really helps give you a grounded feeling.

If your diet was junky before, then this could be too cleansing, and that could be why you feel so rough. Big changes usually throw your body for a loop.

I don't have a complete answer, these are just a few ideas. You should ask this question in the Ask Shelley forum, she and others can give you much better feedback!
~Squeaky