How long would it take for your body to feel weak once going vegetarian?

I recently went vegetarian a little over a week ago. I feel completly fine. How long would it take before I feel weak?

Thanks :)
You should, in fact, feel the opposite happening to your body. My father, who used to be a huge meat consumer and has been a huuge athlete all his life, stopped eating all meat at age twenty, and immediately began to perform even better in sports. I