Are you back with the same tiny company of like 20 people? How many bosses and managers are there? Sounds like there are more bosses than employees! No wonder you are stressed. Too many bosses.

It does take time to build confidence in a new job. Even if it’s not fully new, your previous employment there was not long either. So it’s all relatively new. It takes time

I’d be mindful about sharing too much. Unless you are asking for official accommodations per ADA, it might be wise to keep PTSD or being bullied in other jobs or personal issues to yourself. At least for now. It’s too early on to tell them too much about yourself.