Well, you didn't say what your job will be. I agree with SoA, however, in that your job will be different than your training----for one, you won't have the manager breathing down your neck; another thing is, as you start to get in the swing of things, you'll be able to do things according to your own "rhythm", so that'll help.
Try not to worry about it, too much----unless your manager is a total pooter-head, they realize that there's a learning curve, and that not everybody picks things up, in only an hour. Try to talk to yourself, and say things like: "This is it----this is gonna be great----this'll provide me with finances help----this'll give me more freedom to buy some "happy" things, for myself....." "Okay, I'm just gonna go in there, and give it my best....."
I understand, though, our brain just doesn't act / react as quickly as we'd like it to----just, hope for the best!!
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White female; age 59; diagnosed Aspie.
I use caps for emphasis----I'm NOT angry or shouting. I use caps like others use italics, underline, or bold.
"What we know is a drop; what we don't know, is an ocean." (Sir Isaac Newton)