Account wants me to change password, but I can't remember my old email.

I created this account way back in early 2014 and by now I have forgotten the password for the gmail. A few days ago, I tried logging in and it said "Update your password" and it refuses to let me log in PSN. I tried recovering my gmail, but nothing. I tried contacting playstation through live support, and the serial number I created my account with does not work. I can prove it's my account because it has my facebook picture with my face. Is there a way I could recover this account? What if I actually made the account on PC and not a PS4?