If you quit SSRIs cold turkey then you're going to wind up with discontinuation syndrome (aka withdrawls). This is going to vary depending on the person so I am just speaking from personal experience. Typically this will mean your depression or anxiety comming back with a vengance. In my cas it hit way harder than it normally does when I'm just at my baseline unmedicated. I also got extremely agitated over the most minor things. Plus you've got all of the physical symptoms such as tremors, nausea, and bouts of cold sweats. Then you have the one withdrawl symptom that is unique to meds like SSRIs which is brain zaps (aka brain shivers, brain flips brain shocks). Brain zaps are really hard to describe. The best equivalent that I can think of is when you get your reflexes checked and you feel that reflexive muscle twitch; it's basically that feeling except it feels like its comming from right in the middle of your brain and it happens about once per minute for the entire duration of the withdrawls (1-2 weeks). It's not something that is painful but it is annoying, constant, and highly distracting. Basically every time one hit I would lose my entire train of thought which made it impossible to focus on even the most basic things. From what I understand noone knows what actually causes the brain zap sensation but one of the leading theories right now is that they're basically just micro seizures.