Uterine shedding or possible miscarriage?

I wasn’t sure where to post this. I had my son in October and had my first period about 3 weeks after having him, I spotted until December it stopped for about a week then I got my nexplanon put back in my arm and started spotting a couple days later, I kept spotting brown then on the 10th of this month I started my period again without any breaks of spotting and today while I had my tampon still in this came out.....I’ve been cramping horribly and having hot flashes, I’ve never had anything like this so I’m not sure what to think