Just want to echo what Peppermint Tea said about bugs going around. They certainly are in my area. Either it's a varied range of different bugs, or people are having widely varied symptoms to the same bug. I had a "cold" with a productive cough that started in early December. After 3 weeks, I went to the ENT who assumed it was a secondary bacterial infection and prescribed 10 days of Augmentin. Finished it Monday morning. It's Thursday and I still have the cough, although the congestion has gotten better.
When I first got sick in early December, both my parents had it before I did. For the most part, they seemed to get over it. Then, last week, the relative we're living with got bedridden with vomiting and awful back pain. She insisted it wasn't the flu and that it was related to whiplash from a fall she had on Christmas Eve. I still believe she had the flu or a stomach virus. Pretty much as soon as she was up and around, my 93 year old dad got sick again with a productive cough. No fever. No body aches. Not bedridden. Just a cough that increasingly gave him anxiety and trouble breathing over a period of days (not hours). Mom took him to the doctor yesterday. Doctor had him admitted to the hospital, where (surprise), they actually swab tested him for the flu. He was positive for both influenza A and B.
Whether all 3 of us have had the flu or whether my relative had the flu as I suspected, we'll never know, as none of us were tested.
IMO, doctors are still heavily relying on old symptom pictures to guesstimate what type of infections people have. I suspect newer strains of bugs are producing newer and more varied symptoms.
Lyme is well known for causing neck stiffness. Meningitis can also cause that. Meningitis can be bacterial or viral and can be very dangerous. I've never had it, but what I can recall about hearing of it is it usually causes "the worst headache you've ever had in your life." Use your best judgment as to whether you need medical attention. If you do go somewhere, insist on a swab test for the flu. If it is the flu, they can give you Tamiflu, but you have to start it soon after onset of symptoms. Sorry for the book😌