You may have correctly drawn the angle in standard position, starting on the x-axis, moving clockwise, and ending in the second quadrant. However, the reference angle is the smaller angle formed by the terminal side and the x-axis. It has a value anywhere from $\displaystyle{{0}}^{\circ}\usepackage{cmbright}\Huge\$ to $\displaystyle{{90}}^{\circ}\usepackage{cmbright}\Huge\$ . You chose the larger angle formed by the terminal side and the x-axis.