What causes severe headache, stomach pain next to kidneys, tiredness and painful heels on a child of 10 years of age?

That is: way too difficult to answer in this forum. I strongly suggest you take this child to a pediatrician especially with the description of "severe headache" which is unusual for a 10 year old. There is no obvious connection leading to a single diagnosis in your list of symptoms which is why it is imperative that this child be seen and examined by a physician.