I started a new job over a month ago, it was just what I was looking for and within my capabilities. I think I'm going through peri-menapause (I'm awaiting blood test) but I just can't seem to concentrate properly on anything, I have terrible brain-fog. The feedback so far is good in some ways but my immediate line manager has found me slow to complete projects and there's a few things I've forgotten. I've always been very organised and I'm just mortified, what's worse is I don't feel I have the capability to improve right now which is making me really anxious and affecting my sleep. I don't want to lose this job, I can't afford to lose this job, but it just feels like I'm in a downward spiral. This morning I feel almost to anxious to go in. What the hell do I do? I feel like a completely different person to the happy and confident woman who went for an interview a few months ago and I know they must be thinking the same.