I am fairly new to SS, going through my LP right now.
Regarding overtraining-you haven't. In college I did an incredibly high volume, 4-5 day a week Russian program for 4-6 weeks, followed by a bench every day program for a month.
Literally every moment I was not in the gym, at work, or at school I was asleep. At least 6000 calories a day and i still couldn't handle it. I ended up entirely losing my appetite, getting sick, and getting very, very tired, all the time. It took 2-3 months for my appetite to come back.
Nothing that I did was wise, but it did teach me what overtraining feels like.