Has anyone found a skill or something that gets you out of "shutdown mode"?

I mean like, this goes for everything, even like basic hygiene and other simple tasks, but I'll use the example of college work. I start the semester, I'm staying on top of classes and assignments and everything, doing pretty well and feeling like maybe I can actually keep this up, yay. High anxiety but I'm doing well so fine, it's stressful but I'm being productive. Then don't do so well on something. Setback. Stress goes up. Spend more and more time trying to manage stress than actually being productive. Fall behind. Stress keeps going up. Going from being overwhelmed to just completely shutting down, doing any work at all is this most daunting and stressful thing in the world, gets to the point of not even trying to do graded work. Telling self I "need" to do something accomplishes nothing, can only manage to stay in bed all day watching comedy on Netflix and snacking.

Like it's literally like I can't "tell" myself to do anything anymore? The connection between my conscious thoughts and what I actually do is shut off?

How do you get back on top of things when you can't tell yourself what to do???

Who else is in this mode all of time for years and years and years? Anybody? I feel like I never get more than MAYBE a month or two of "barely normal level of accomplishing SOME simple tasks" and then the entire rest of the year is "shutdown mode". Just like a total retreat from reality and having no "rational" control.

I can't even explain it.