wtf is up with my period

So I had my daughter around 2 months alomost 3 months ago. Today I got my second period since having her. Well when I went to check my pad today there was this thing on it that kinda looked like a sac and it was filled with dark blood. Does anyone know what this is? Its really freaking me out. The sac was about the size of a quarter.

Probably a blood clot!

It's a blood clot... you shed uterine lining during your period. You shed more for a few months after having a baby.

Sounds like a blood clot to me. I get them all the time when I'm on my period.

The only time to really worry is when they are very large or you're passing tons of them.