Symptoms of an invasive yeast infection can be vague and depend on which part of the body is affected. Common symptoms include fever and chills that continue after you have taken antibiotics.
---Source: WebMD---
If you are running high fevers, that sounds like an infection of some type. A stiff neck and fever is the classic symptoms of Meningitis. Go to the ER if you need to.
I doubt that Candida would cause a high fever.
See another doctor, this sounds pretty serious.
Candida could be an issue, so can food allergies. If you haven't, ask for a complete blood panel to rule out anything serious plus the Candida test.
Many if not most of your symptoms are consistent with systemic candida symptoms.
You absolutely need to rule this out, however, for now I would suggest you consider getting Prebiotics and Probiotics asap, the best quality possible.
Your intestinal flora needs to be repopulated with healthy bacteria, since you had so many rounds of antibiotics :( and other potentially harmful drugs.
Blood tests and stool tests can miss this, so don't consider it ruled out if your results come back negative.
A strict anti-candida protocol (no yeast, no carbs & sugars which feed the candida, taking pre and probiotics & coconut oil-the best natural antifungal- lowering stress) will help expedite your recovery, should you indeed have this infection, but please note that it will take quite sometime to eradicate.
You also need to rule out Obstructive sleep apnoea, which could be related to inflammation of your sinuses with many possible consequences and complications.
Are you a mouth breather? Do you often sleep on your back?
Do you snore when you sleep?
These are common signs of OSA.
An ENT would be the one who can diagnose this.
I hope this helps, however, my suggestions and comments are not intended as a replacement for medical advice.
Best Wishes.
Niko