What is this?!

Kayla • 💍Engaged to the love of my life | 🌈🤰Ronald Allin Shelton 5/6/2020

My discharge is so heavy you'd think I was on my period. But its watery, thin, DARK brown discharge with an odd sweet smell? Anyone had this problem before? I went off the depo after my first shot in July but havent had anything like this before-I had mirena before the one depo shot as well if that makes a diff