All I will say is that this will pass. Eventually you'll acclimate to the job and it's requirements and do just fine. I am always awkward when I start a new job but usually wind up being one of the best employees so long as I have a manager that meshes well with my quirks (not a intense, angry sort of person but someone who makes requests calmly.) All you have to do is figure out a system for what you need to do and implement it. At my job I have done just that and many of my adaptations have become the default way to do certain things since my way works quite well. Just give it time. You can also see it this way: If you want to quit, just work there until you get a new job or they fire you. The extra time spent working will put more money in your pocket, money you otherwise would not have had. In the end, whether you get fired or quit, the result is the same: You have no job and you don't matter to the company. Why not milk as much money out of them as you can in the mean time?
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Uncertain of diagnosis, either ADHD or Aspergers.
Aspie quiz: 143/200 AS, 81/200 NT; AQ 43; "eyes" 17/39, EQ/SQ 21/51 BAPQ: Autistic/BAP- You scored 92 aloof, 111 rigid and 103 pragmatic