How can i figure out where my depression/racing mind/anxiety started?

PsychoTherapy: Oftentimes it's hard to figure out the beginnings and origins of symptoms. In a nutshell, psychotherapy or talk therapy might help with that. One of the ways to do this, is to look at the patterns of your behaviors -- by keeping a journal and trying to make connections between past and present behaviors. Good luck!

Agree w Dr Fox's: recommendations but also strongly encourage comprehensive physical and psychiatric evaluation.