There are legitimate reasons for having one party consent legal. My experience with employer harassment has been that it’s extremely hard to prove discriminatory behavior without being able to record without consent.
*before you REVEAL that you did it
So it's better to talk with a laywer and get informed of your options and the risks, and how to go about it, before you do it, not merely before you reveal you did it.
Don't keep the recordings on your phone.