Well with an impact at the back of head and history as mentioned, I would advice for an urgent MRI cervical spine
to rule out an cervical spine injury
Numbness of hands and pain can be a result of it. Also is there weakness of hands along with numbness?
Get a MRI and see a Neurosurgeon at the earliest.
I understand you have your liabilities but you also have to look after your health.
You need cervical immobilization with rest and use of cervical collar
Simple cases of inflammation usually subsides with oral analgesics- anti inflammatory agents, Vitamin B12
may be required as well. In some cases depending on radiological and clinical evaluation surgical interventions may be required.
Whatever let the doctor see the MRI and do a proper clinical evaluation to arrive at the diagnosis and line of management.