Numbness in the fingers is not typical of an infection, or a typical viral infection, therefore, further evaluation is needed immediately.
Viral infections are not typical without abatement for 12 days running, so an unusual problem, bacterial infection, etc....need to be fully ruled out.
I do believe you need further work up immediately, and that this should be an ER visit.
Not only pneumonia, but ascending neuropathy, myelitis of the cervical spine, and other more serious problems need to be ruled out at this point.
I would not wait.
Prednisone is not indicated at all without a diagnosis.
This might simply cover up symptoms. For example, cervical spine disease would require an MRI to evaluate, or it could progress without treatment.
See this fact sheet
See this long list of hand/finger numbness causes from the mayo clinic
I am a double board certified US clinical doctor.
Very familiar with these presentations.
Find me anytime in medical.
Please click a positive rating on this answer page if you appreciate my answer and would like credit.