You've just stopped an addictive drug cold turkey. You're having a long withdrawal, which many people do who come off of addictive drugs such as nicotine, benzos, opiates, alcohol, and even antidepressants. Stop Googling symptoms --- Google is great if you have a diagnosis and want to see if your doctor is a quack, but it's not so good just to google symptoms. So many diseases, so many symptoms! Hopefully this will pass quickly, but look at this like combat -- nobody truly comes out of combat the same as they went in because of the intensity of the experience. Addictive drugs are an intense experience that the brain has trouble doing without and adapting back to operating normally. Sometimes it's quick, sometimes it's not. Hope you're on the quicker side. Meanwhile, if you're able, stay busy for now so you don't spend a lot of time obsessing over it, and you might look into meditation, which can help with patience and acceptance if it takes. Good luck.
It goes away slowly. I still have anxiety but not as severe as 6 months ago. Hang in there. Congratulation on quitting!!
I feel for you. I'm on the same boat and I am exhausted.