Hello, You are having severe headache after hitting your head. You are presently experiencing severe headache, weakness and feeling sick. You might have got a mild concussion and hence the symptoms. Sometimes, people feel the hurt for several days even if there is no concussions, as the bruised tissues may take some time to heal. You can apply ice or cool compresses off and on, keep head on a pillow when you sleep. Since you hit your head, you are suggested to get basic neurological test, neuroimaging tests, MRI scan or CT scan done to rule out or detect serious injury, like bleeding inside the skull. If the scans show visible injury, mild traumatic brain injury (TBI) may be suspected. If the scans show no visible injury, the patient will be evaluated for concussion and treated accordingly. In the meantime, you are suggested to give yourself rest (both physical and mental). Avoid doing exercises or physical activities for a couple of days. Stay away from any type of eye strain like reading, watching TV, or using a computer as your symptoms can worsen. Avoid activity that can cause further head injury, including riding a bicycle, roller skating, etc. Get clinically assessed by a Neurologist. Get treated at the earliest. Take care. Hope I have answered your question. Let me know if I can assist you further. Regards, Dr. Nupur K., General & Family Physician