If my jaw is struck by something(accidentally) not yet broken, and later i trip on something, without falling, could that cause a jaw fracture? i have been getting a lot of pain and numbness).

Post-traumatic TMJ: syndrome. After CT imaging and physical examination have excluded structural damage, management depends upon the particular type of TMJ disorder. Many posts-traumatic TMJ patients frequently have accompanying symptoms of TMD and should be referred for appropriate management to a TMJ specialist.

Possibly: If you are concerned I would not hesitate to be seen to have this ruled out.