Playstation network signed me out?

So I recently turned on my PS4 & my PSN account was signed out, unfortunately I don’t know my password nor do I have access to the email address associated with the account. I’ve never experienced this before though so I’m curious as to why my account was signed out? My account has remained logged into without requiring authentication for over a year..

So I have three questions,

#1 – If I were to be banned from PSN for whatever reason, would I have been logged out automatically, or would I be prompted with a dialogue stating I’m banned.

#2 – Is this normal? Is it a regular occurence for you to be randomly signed out of PSN ( I mean I would assume not, since I’ve been logged in for over a year.

#3 – Is it possible someone changed my password whilst I was inactive? and so due to crednetials changing I was signed out to reauthenticate my credentials.