Many, many, many quitters have had the same complaints you listed. Quitting is a huge life change--no matter that it is a healthy thing to do, the chronic dependency on nicotine that developed over years takes time to get over. It's not just psychological or emotional--the dependency was born out of hundreds of thousands of doses of nicotine to the brain. The brain remembers.
Good news is that smobering up (Becoming and Ex) is doable one day at a time.
At 54 I quit. Cold turkey and mostly on my own. I would have been better off seeking and keeping good support such as Ex. All I can say is stick around to find out why you were right in the first place to quit.
Welcome to Ex. Below are links to blogs by fellow Exers--please give them a read, you might find them helpful.
https://excommunity.becomeanex.org/groups/newbie-quitters/blog/2019/01/27/one-of-the-greatest-tools-... by Jackie
/blogs/Mandolinrain-blog/2019/03/08/evaluate-your-quit by Mandolinrain
Dopamine - the Double Edged Blade by Thomas
