Starting new assignment at work tomorrow

I'm getting ready to start a new work assignment tomorrow. I'll be in training for a very long 7 weeks. I've been very stressed and anxious at work and my ability to do my job has been lacking. My mind goes blank, I'm always in a brain fog, I'm always stressed, anxious, fatigued, exhausted, and certain things about it are very embarassing at times. I got my drug test yesterday. We have to get one for each assignment. I'm not worried about that at all. I'm a recovering chronic alcoholic and have been sober a very long time. I don't do drugs. The only thing that might show up is the medications I'm prescribed by my psychiatrist or my regular doctor. I am nervous about this training and if I'll be able to do a good job once training is over. I'm 48 (almost 49) and really struggle lately with this brain fog business. It does awful things to my body as well. The stress and anxiety get so bad that I wind up becoming very ill. I also have to consider my disability benefits because I don't want to lose that. I cannot live on disability alone, though. It just does not pay me enough to live on. I have to try my best at this job but it's very difficult for me with my mind and health the way it is. I'm concerned about things like dementia. Something to think about. Where is all this brain fog coming from? I'm going through menopause and I heard that sometimes happens with that. The hot flashes are awful and really wear me down. Anyway, those are my thoughts for today. Hoping this job will work out good for me. The other assignments I've had have not been that great. Hope everyone is doing well.