There are all kinds of different diets for loosing stone in a few days but when my girlfriend tried few of them there was no sucsess. It doesn't matter are you vegeterian or not because most of them don't include meat.
Do you eat fish? Or no meat at all? Are you using some kind of suplements for nessery proteins?
Than my sister tried to eat normal but after 6:00 pm nothing. This was her only rull. And it worked. In the begining she was so hungry and she was drinking pleanty of water to full the hunger. After three days it got a little bit easier and she wasn't that hungry anymore.
One of her friends tried with shakes which are containing natural ingrediants and she said that she has lost a stone in a 15 days.
So you could try with either of this solutions or find some other alternative. If you do and your results are sucesufull please share with us.