Hello dear,
The symptoms as mentioned in your post can be attributed to either nerve compression or any intra-cranial complication secondary to the
head injury &
hematoma.
The scalp hematoma is due to accumulation of fluid and blood.
The blood cells which gets accumulated are eventually broken down and absorbed in the body.
But this is a slow process & takes times to disappear completely.
Till that time, symptomatic relief is obtained by taking analgesics, muscle relaxants, ice compression & adequate rest.
However, if the symptoms still persist or associated with any other complaints like
vomiting,
loss of consciousness, convulsions, etc., then it will be better to consult your Physician.
Investigations like X ray of the head & neck region and
CT scan will be helpful to rule out any intra cranial injury.
There is no need to worry, you will be fine.
Wishing you a good health.
Thanks & take care.