Hey man- not sure if this will make you feel better... But I'm exactly where you are. I quit weed at the beginning of Feb. 2017... insomnia, anxiety, ringing in the ears (known as tinnitus)... I can't exercise either... yet it was a huge part of my life. I have hot/cold flashes, the night sweats, even odd muscle spasms.
Lurking through this forum, I found other people who quit, and they all have the same symptoms you describe. Including the idea of feeling this way forever (I've had many panic attacks about this. Convinced this is source of anxiety).
You're not in this alone. And, what gets me through another day, is reading all of the success stories on this forum. Look up usernames biggiesize and wakinglife. It's what gets me through. They make no mistake in writing that recovery from weed is an extremely slow and daunting process. The brain will heal (think of everyone who has suffered a concussion who go from zero to 60 in six months to a year and make a full recovery). Apparently it will take a long time and require patience. Use this, as I do, as a remjnder as to way you never want to touch that stuff again. Because when you do heal- why go through this crazy anxiety again?
Best of luck to you and keep posting here. It's what I'm doing. Believe me, I'm currently a shell of my former self. Back in January, compared to now... night and day. But one day at a time. Again, look up those usernames, I read their journeys when I feel like utter crap