It really sounds like something is wrong with your meds! Seriously, they need adjustment. Even if it means going to the hospital before your p-doc appt. Everything seems much bigger and more catastrophic when your meds are making you feel terrible. I know!
Please don't give up. Please call someone who can help you. Your hopelessness is not a good sign. Therapy will help you to retrain your cycle of thoughts at some point in the future when you're stable. But your meds are not helping you to be stable as far as I can tell. My thoughts get out of control too when my chemicals are messing with me.
You shouldn't have to suffer like this for 6 more days just because that's when the appt is. If it's unbearable, get an emergency appt or go to the hospital.

We all care about you.
Stay in touch, okay.