College Education Expense

I have a 1098T showing I paid $10,600 in expense box 1 for my son college   I have a 1099Q from 529 plan showing I had $ 9,150 paid to me the dad.  In the worksheet for the regular tax it drastically reduces my expenses from 10,600 to like 600 as qualified expenses.   Thus making the prorata earnings portion of the 529 distribution taxable income to me.  Why?   My son's expense way exceed the reimbursement withdrawals I made from the 529 account set up for his benefit.