Mailbox empty after account recovery.

I tried to log into my account and was told to re-type my password and a series of characters to verify I'm "not a robot" because someone had been trying to access my account unsuccessfully.  I couldn't get the password and the series of characters to work (after multiple tries) so I clicked on "Can't access your account?" and was asked to reset my password, then verify my secondary email address and phone number.  After I did that, it took me to my inbox which was completely empty - none of my emails were there nor were any of my folders I had created.  I then proceeded to receive two new emails that someone who had just opened an account would receive.  I have had this account for 10+ years!  I need to recover my emails - I have some sensitive information in there that I desperately need access to.  Please help!!!!