Hi Emma, you really need to get checked out,as soon as possible, you dont need to be big or old to get diabetes, there is obviously something not quite right so you need to find out why you are getting these symptoms. Type 1 diabetes can happen at any age from early childhood, though it is less common in people over 35 but it still happens.Type 2 is also happening in younger people too. Go to your doctors double quick, it's better to find out than to sit and do nothing, If it is type 1 you will get very ill if not treated, and don't worry about being paranoid your doctor would rather be safe than sorry. Hopefully all will be ok, but it's best to find out . hope all goes well and you are feeling better soon.