Why is the ionization energy of nitrogen higher than that of oxygen, in contrast to the general trend seen for ionization energy?

Nitrogen - Electron configuration [He]2s22p3 has three electrons in individual 2p orbitals with adjusted twists since electrons attempt and remain as far separated as could be expected under the circumstances. Oxygen - Electron Configuration - [He] 2s22p4 must put 2 electrons in a 2p orbital with inverse twists. This causes a slight shock between these electrons which is more prominent than electrons in independent orbitals making this electron somewhat less demanding to expel.