Friend and i knocked heads yesterday's really hard.got an instant headache. i still have headache and now when i chew it hurts. also stiff neck.

Post traumatic HA: Head hits can lead to daily headache, plus muscle tightness of face, jaw and neck. Likely this will resolve on it's own within 4 weeks or less. For the first 2 weeks, it's okay to take over-the counter Ibuprofen or Naproxen as needed. If it persists beyond 2 weeks, get in to a neurologist for evaluation and management. Good luck!