This might have been a full on respiratory alkalosis panic attack especially if part of your body was going into spasm. Were you having muscle spasms and increased pins and needles, and a sort of lightheaded brain fog with pins and needles in the face and such? The most important thing in that situation is to BREATHE SLOW. People typically yawn because your brain is not getting enough oxygen, and respiratory alkalosis causes you to not get enough oxygen. It's counter intuitive how hyperventilating can deprive your cells of oxygen but trust me too much oxygen and not enough CO2 leads to your cells not being able to get any oxygen (because your body also needs CO2 to get oxygen into the cells). I think at this point you're having so many symptoms that are feeding back into each other, the main one I can stress the importance of from personal experience is chronic pain and neuropathy.
Not being able to get comfortable ruins sleep, it fragments it and the pain and stress fills your body with adrenaline and anxiety, and then the anxiety patterns stick. I know how it feels like you should be asleep because you feel absolutely fried but basically adrenaline is what's keeping you up. I can't stress enough how important sleep is, I'm sure you realize this by now. I really think if your doc has any brains at this point they will order a sleep study to rule out sleep apnea. Sleep apnea does cause sleep paralysis as well. There is also a connection between sleep apnea and MDMA (MDMA appears to cause obstructive sleep apnea), and yes skinny people do get it, I had it as a skinny young person myself because I had a deviated septum, and there is a connection between sleep apnea and neuropathy (and specifically thoracic outlet syndrome which might be contributing to your hand neuropathy, some thoracic outlet syndrome has been shown to get better when the sleep apnea is fixed). So a sleep study is very much in order to rule out sleep apnea. What's interesting is Mirtazapine is being investigated as a treatment for obstructive sleep apnea. Anyways, if I were you I would definitely go back on the Mirtazapine (if not Trazadone or low dose Seroquel). If you're in America and have a little money a new medication called Belsomra might be worth trying, it's nothing amazing and some people have bad reactions (at first I got increased sleep paralysis, though that went away) but it's not really addicting. If you ever get really suicidal and really need some sleep there is always Ambien extended release and Lunesta, combine that with Trazadone and you should be knocked out. Clonidine is definitely something you should try as well, and I would take it with extended release melatonin because Clonidine can mess with melatonin production (you should try extended release melatonin by itself anyways, it really helps some people after MDMA because MDMA seems to mess with melatonin)
I should mention at this point the chronic deconditioning is probably getting very real and lack of bloodflow is contributing to ALL of your symptoms. I really can't stress enough how important motion is for the body, and if done early enough in the day cardio has been shown to greatly increase sleep and smooth out sleep structure, and there are many many anecdotal reports of cardio helping with sleep. I know it's hard when you are injured and in pain to do cardio but at some point it might become worth it to bite the bullet and try it for a couple months and get the blood flowing: cardio tells the body to make new cells and regenerate the old ones. Being deconditioned will in general ruin your health but it will also ruin your sleep and make you prone to panic attacks and hyperventilation syndrome.
Most of your growth hormone is released during sleep so it's really important to get good sleep when you're trying to get the most out of exercising (and lack of sleep generally leads to deconditioning anyways). I would really view this time off of Mirtazapine is a little tolerance break, I would get back on the Mirtazapine and get a little sleep under your belt, the start digging into the cardio, mindfulness meditation with deep diaphragmatic breathing, and find a better doc! Massage and physical therapy should also be on your mind, mostly physical therapy. I can't stress enough how important it is to figure out where your neuropathy is coming from, it was a real chore for me to figure out where my neuropathy was coming from but it eventually turned out it was thoracic outlet syndrome.
The nerves to the arms/hands get pinched by the ribcage and breathing muscles and the nerves to the face can also get compressed by the breathing muscles in the neck that are called Scalenes, which currently I'm dealing with that and the resulting jaw problems from Scalenes because they attach up into your jaw area, which it sounds like you could be dealing with as well. This is common with people who have anxiety because of the breathing component. If I were you I would get some physical therapy and a neck MRI under way, if if seems your problems are from thoracic outlet syndrome then you should find a physical medicine doctor who can inject your scalenes with Botox so we can take the pressure off all your nerves for a bit. Many people report their jaw problems get better with scalene injections as well.
Anyways, we gotta get to the bottom of your physical pain, I think it's messing with your sleep and causing you anxiety. Take care of yourself, I hope you start to find some relief soon. Don't be afraid to take the Mirtazapine or stronger stuff like ambien once a week or on the day after you try to work out. It can help to know you have something on hand if you really need to sleep as well, or to know that you have something on hand to get some sleep after doing cardio so you get the most benefit from it.
Take care of yourself...
