Google myasthenia gravis and visit some of the websites. You do have some of the symptoms and they have some blood tests you could ask for if you think you may have that. You could just have essential tremors too but your neurologist should of said that. It helps to get a second opinion neurologist. I had to go through all of this to find I have both disorders. Your best bet I’m sure you’ve heard is to quit smoking as none of the neurological disorders do well with it. I hope you can get to the bottom of it