Feels like a flare, but normal labs.

I was diagnosed in 2010 and went through the normal treatments. Steroids and some type of imunosupresant drugs. Ive been on Methotrexate, Azathioprine, CellCept, Abatacept, Rituximab, etc
I've been going through a weird flare for a while now. I had some sinus symptoms and was on Bactrim and Prednisone which worked for the sinus symptoms, but nothing seems to work for the worst symptom which is just feeling terrible.
I told my doctor that I feel like I have the flu combined with a hangover. I feel like I've been poisened. Or what I imagine being poisened would feel like. The doctor said it's got to be a Wegener's flare. But my sed rate and anca are normal as are all the rest of my blood and urine tests. They even did a CT scan and an xray and all are normal. I just feel terrible, plus I have sever peripheral neuropathy.
I'm now taking prednisolone and Leflunomide for the flare, and I'm about to start Nortriptyline for the pain.
So, my long winded question to you all is this:
Do any of you ever experience a flare but have normal labs? And do any of you have non specific symptoms such as just feeling awful but without the typical symptoms.
Thanks,

In the past my symptoms often preceded my lab indicators. The doctors started treating when the symptoms became present cause they knew the lab indicators would confirm things in a few days.

The other thing is that residual symptoms which are troublesome can occur even when other indicators suggest a drug induced remission. Not everyone attains a symptom free remission. It does usually suggest the disease process is mild or minimal in the damage it is causing but you can still feel pretty rough.

lab results can also be misleading at times and fail to detect a flare even when your body tells you and the doctors who listen that things are not well. That is why it is good to have an experience doctor who knows about GPA and how it might act since people often vary in their responses to the disease process and treatment.