How do i find out what my last password on my email account was

Today in the morning all my emails were deleted off my phone. Then I tried going on the computer and tried to log in to my live account and it was saying my password was incorrect maybe I had forgotten my password as I usually don't login to a computer and my phone always has my emails or maybe someone changed my password over night. I reset my password using my security question. I need to know when the last time my password was changed. How do I find that out. Its for the security of my account.