I want to start off by saying congratulations on getting the new job, please feel proud of yourself for achieving that. To go from a period of time out of work to employment shows enormous strength of character and determination. But for the very same reason it is no wonder that you are feeling anxious; to go back into the workplace after time away is tough.
I used to be line manager and I can tell you one thing that I used to tell the people I managed: I would rather you asked the same question 100 times to get it right than say nothing and struggle. People take different amounts of time to learn things and it's ok to make mistakes (even if you've been in the job for years). If a manager tells you off then they need to take a long hard look at themselves first to identify if they could have provided better support in the first place. Do you have review meetings at work at all? I mean one to ones with your line manager? If you do how frequent are they and do they give you the opportunity to discuss the things you're doing well and the things you need more support in?
There are things that can be done within the workplace that can ease the anxiety you're feeling (the one to ones described above) there's also the emotional support you may need outside of work to build your confidence. Do you have a partner/good friend you can talk to about your worries and if so does it help to talk to them? Do you still go to counselling sessions? If not would you consider trying to get some more counselling? To me it sounds like you may benefit from psychotherapy rather than counselling, such as cognitive behavioural therapy (cbt), as this can provide you with different ways of managing difficult experiences and emotions.
While you're trying to figure out things to help keep you in the place you want to be remind yourself of how courageous and determined you have been I'm getting your new job.
Big hug x