Adrenaline spikes: Med detective needed, award given

I'm desperate for help. If I was rich, I'd pay a million $ to get answers. It's hard to summarize: I am a 59 yr old woman. 8 yrs ago I started having what feels like strong adrenaline rushes during the night and especially in the early morning. They disrupt my sleep making me severely sleep deprived. It used to happen a few times a month but in the last year, has been happening daily. This is not as simple as anxiety. My life is not particularly stressful compared to years ago and I've always handled stress well. Physical symptoms come first, then anxiety from adrenaline comes after. On rare days, If I sleep through the night, I wake with excess adrenaline and will be hyper the whole day and evening. Sometimes, I will have a severe "crash" in the afternoon with all kinds of symptoms that have me couch-bound. I take a tiny dose of Amitriptyline (10 mg) before bed to help with sleep, but it's obviously not working well enough. I am on Synthroid for non-Hashimoto's Hypothyroidism since 1996. Despite being 59 yrs old, I am not yet officially in menopause (last period was May 2017). TSH, fT4, fT3 are normal. Urine catecholamines (epinephrine & norepinephrine) are normal (although that does not necessarily reflect what is in the brain). Plasma ACTH is normal. I've tested negative for autoimmune disorders. Cortisol was high a few years ago (34.3 mcg/dL) but it's currently high-normal. DHEAS normal. Accompanying the start of this was phantosmia and occasional RLS. My diet is excellent, including a few good supplements. Until last yr when it started happening daily, I was exercising 6 days/wk. I cannot tolerate it any more - any exercise beyond mild cardio/aerobic causes an increase in symptoms. I meditate and have tried all kinds of herbal teas. I've experimented with different possible solutions, to no avail. I'm a voracious researcher (only legit sites) and still cannot figure this out. I'm normally a positive, active, happy person who loves to help others but this is ruining my life. I cannot make any plans, cannot get my work done, cannot even visit friends. I had to stop my volunteer work with children. 🙁 I'm starting to become depressed and hopeless. I've been to a total of about 9 doctors about this problem and they just shrug their shoulders and send me hope with more disappointment. The only help offered was an addictive prescription for benzos but I refuse to be treated for something without knowing the cause. Ideas: an atypical tumor on my pituitary or adrenal glands? Maybe, but I can't get a doctor to order the necessary MRIs. Perhaps not endocrine but a sleep disorder? High A.M. adrenaline is typical for sleep apnea but it should not cause these severe symptoms, and I really do not think I have sleep apnea (I don't have other symptoms). A neurological disorder? Maybe, but I can't get a doctor to order an MRI of my brain to make sure my pituitary gland is okay. If you've gotten through this far and you have any thoughts, please chime in. If your idea leads to a proper diagnosis and I get well (or treated properly) I will be your slave for life 😉 Okay, seriously. I'm not in a good place right now.