I am SO scared!!!!!!!!!!!!!?

I am 14, and I am in year 9. Anyway, we have been doing revision and loads of stuff to get us ready for our GCSE's. Because I have my first GCSE exam in June 2010. (science) anyway, we have three teacher one for chemistry, one for biology, and one for phsyics. We have done chemistry and physics, and biolgy in one section of my GCSE, we have revision guides. And there is chemisty 1, and then physics, and biology 1. And the same but just 2. We have done all the c2 and p2 and b2 now. And I THINK we will probabily go onto c1, p1, and b1 now, because we are moving around cles next. And I go to chemistry and then physics, then biolodgy. From the revision books that I have. It says in Biloogy we have do to things with weight, and health, like smoking and drugs/alcohol and other stuff!!!! Our teacher says there are things called "can do tasks" which basically we do, like expreiments and stuff and they give us some marks for our overall score. Like we have our GCSE exam (paper) in june and we have coarsework, and these can do tasks. I am really worrying incase one of the can do taks in biology in this next unit we MIGHT be doing, which i think we will be doing. I am scared if we might have one of the tasks for us too get weighed!!!!!!!!!!!!!!!!!!! And I am big. I am 14 and I weigh 200lb exactly which is 14 stone 4 lbs!!!!!!!!! And I don't want to get weighed!!!!!!!! I would probabily cry!!!!!!!!! And people would be mean!!! I am on a diet now, and I want to lose like 2-3-4 stone. Sometimes I look ok, I have a lot of muscle on the back of my legs (the bottom part of my legs) and I do exersise at school when I have PE. Also sometimes the clothes I wear (depending) sometimes makes me look ok. I am a size 14. But some things I can get size 12. I do have a pair of trouses that are size 10. I really don't want to get weighed!!!!!!!!!!! How can I lose weight, and fast???? + this is so random, but does porridge have a lot of bad things in , or is it healthy???? Like I wa thinking of having porridge for breakfast everyday, and a cup of tea, and then lunch I would get a samwich, no er and maybe tomarto's and a little cheese. Then an apple or banana. Maybe a yogart, or snack healthy bar. Then for tea I could live of soup canned soup and that's it. Maybe some bread, not erd. How is that. + I will be eating soft food soon because I am getting braces on. + I want too look good for when I go on holiday. + I DON'T WNAT TO BE WEIGHED!!!!!!!!!!!!!!!! OH AND I AM 5 FOOT 6.3 INCHES. SO AROUND 5"6'. PLEASE PLEASE HELP!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!…