Could getting hit in the eye area cause brain swelling? how long before that would show up? i don't have a headache or anything. just some jaw pain.

Facial trauma: Any trauma to the face can cause brain swelling or a concussion. You must be cautious. More important you must be evaluated for injury to the orbit and jaw. See a board certified ENT, Oral Surgeon or Platic surgeon. They may want a CAT Scan to evaluate your face for fractures. If you don't have headache or change in vision it is unlikely you have a concussion. But you can see your primary.