Hi there
It sounds like you have quite a few different things going on at the moment, school, family, not eating enough and finding out you are dyslexic.
It can be difficult to deal with lots of things at once and its important to work on one thing at a time. Could you talk to a teacher at school about how you are feeling around your education and see what support the school can offer?
Perhaps once you get some support you can try speaking to your parents about the pressure you are feeling.
It's important for your health to make sure you eat properly. If you think of food as fuel for your body, not eating enough can make you feel worse, worn out and tired. For more information about healthy eating take a look at www.childrenfirst.nhs.uk or www.direct.gov.uk.
I hope this helps and do take care of yourself.
Sam