Dealing with Mental Health in the Workplace

I've always been open with my employers about my mental health.... this one has been causing a lot of stress and dissociative episodes and a panic attack.... and then when I tried to process and still be productive DURING said panic attack, they told me they didn't need me doing that work and if I wasn't going to do actual work I need to clock out and go home.... but I need to do the paperwork at some point or another.... and instead of completely not doing anything during a breakdown, I tried to stay out of the way and still get work done that I knew I could handle at the moment.... they keep saying that personal stuff like that isn't supposed to be brought to work and that I should have spent that time of "not doing work" another time, like on my own personal time..... I can't reschedule a panic attack....