Still struggling at work

This coming Friday, I have another capability hearing (second this year). Also still trying to sort out my sickness issue from earlier this year informally. It has taken my company two months to provide me with the minutes of an informal meeting. 

Things are so frustrating, catch up meetings are called at no notice and then I need to explain there and then why I'm making mistakes. 

I'm just feeling so stressed, but I can't take any time off because I won't get paid. So I seem to be in a vicious circle. 

I have started to look for a new job but I'm no spring chicken.