Behind my last tooth in the upper right side it hurts. I'm not sure if it's cut or what not? I have no idea. The pain is going to my right ear

Wisdom tooth. Could be getting ready to erupt or could be a gum irritation or a tooth abscess. See your dentist for an exam.
Dental Exam. Have your dentist take a look.. only way to figure this out is with an examination of the area, with possibly a radiograph.
No idea. I have no idea either. There are many possible causes. See your Dentist. Let him/her directly view the area,and, if necessary, take appropriate x-ray's. Once your Dentist has determined the cause, appropriate treatment can be prescribed.