Hello dear
I understand your concern
Symptoms described by you could be due to viral/bacterial infection,
meningitis.
I would should suggest to consult internal medicine specialist as early as possible and undergo routine blood tests like complete and differential blood count, ESR, blood tests for
malaria,
typhoid, if needed CSF fluid examination for glucose and protein.
Meanwhile,you can continue to take Advil or
Tylenol after some food
Apply
diclofenac and warm pad application on neck.
Other treatment depend on tests result.
Prescribed antibiotic like cerfuroxime will help you
Take proper rest, drink plenty of water, eat healthy diet.
Further treatment plan will decide by complete clinical assessment
Hope this may help you
Contact further if follow up needed
Best regards
Dr. Sagar