Feeling like a failure....

So i have long had difficulty feeling like i dont do what im capable of etc. In may i had major spine surgery (rods and screws to straighten my spine) and i had to get off my meds during the recovery. I havent been able to get back to my dr and so im off my meds now. Im falling apart! School is back in session soon (im a nontraditional college student) and im panicking. We have to move, i have way too much crap i dont need but im so overwhelmed by the idea of going through it all and purging stuff before the move that I just shut down. This has caused my whole house to be a disaster and im so stressed.....i dunno where to start or how to change all this and it sucks....any advice?