increase in income vs. increase in tax bill

Hello! 

My taxable income increased about 11%, but our federal tax owed increased 27%! We crept into the next tax bracket and lost the tuition deduction, but it still doesn't seem right. We went from the 22% bracket to just barely into the 24% bracket. That shouldn't cause this much of a change, should it? Could I be missing something in my return?

Thanks!