Hi Steve! Thank you for your question. I truly am sorry for your injury. Hematomas, the collection of blood under the skin that you feel as a lump, can take weeks to recede and heal depending on how bit it is. If you lost consciousness during the fight or are currently having recurrent headaches, nausea and vomiting, I would suggest that you have it checked by a physician who will do some examinations and request for some tests. If not, a warm compress on the injured area will facilitate the healing of the bump. Also, eating fruits rich in vitamin C can also help the healing process. Just be patient, it will recede in time. If you have any further questions, please do not hesitate to contact me. Take care and I hope you get well soon! Dr. Galera