Hello and welcome to Healthcare Magic. Thanks for your query.
It is very unlikely that the headache which you are experiencing currently is due to the head injury
that you sustained last month. Moreover, the head injury doesn't appear significant and you have already been evaluated by the ER doctors and told that there is nothing to worry.
It is possible that the mild headache could be a result of your excessive anxiety
and tension. Anxiety can present with not only psychological symptoms but also with physical symptoms.
I would advise you to see a psychiatrist
for a detailed psychological assessment and further treatment of your anxiety / panic disorder. There are effective treatment options - in the form of medication or counselling
which will help you overcome your problems.
Wish you all the best.
Dr. Sheeba Stephen
Emergency Medicine Consultant