TMI: thoughts? Advice?

Okay so I know this is TMI. But I’m freaking out. I had my daughter in December. I am on monolinyah pill birth control. I’ve been on it the past 3 months. This has NEVER happened to me before. My period ended the 24th of April, so this definitely isn’t my period. The first picture was yesterday, and the second picture was just now. When I just pulled my pants down to use the bathroom, there was a chunk of brown piece of what looked like tissue. Has anyone ever experienced this or know what it could be? It’s really starting to freak me out.