Thank you for writing to us.
I think that you have injured the back of your head. You can try to ice the area fo 15 mins at a time to see if it helps. If it does not reduce after 3 days, please see a Doctor.
All the best.
These Q&A’s are for educational purposes and should not be relied upon as a substitute for medical advice you may receive from your physician. If you have a medical emergency, please call 911. These answers do not constitute or initiate a patient/doctor relationship.