No, not that sudden, thankfully. Just sometimes something will go wrong and you feel really down for days then pick yourself back up, diagnosed officially as a "depressive episode", during my teens they were much more acute with the feeling of just wanting to kill yourself and possibly taking that step, but then it just changes and you're back to normal next day or in a few hours.
It's often what I've thought about a lot suicides of people my age, as there's a possibility that the person is just acting on auto-pilot under such a dark cloud which might lift in a day or two.