Lactating??

I just got my 4th depo shot (i think) yesterday and on time. I was taking a bath tonight and noticed clearing-white liquid coming out of my boob. My partner and I use condoms/pullout so I really never worry about it. I’ve felt nauseous and had chest pain for the last week or so. I was also spotting with some blood a few days ago. Is it possible it’s the depo symptoms causing this? Or should I be concerned?