After having a child, your body goes through hormonal changes. This can change the symptoms that you used to have with your periods. Intense, painful cramping is normal for many women during their periods. Many women cannot even function during their cramping.

Also, those are not blood clots you are seeing. They are globs of uterine tissue that are engorged with blood. They are pieces of the uterine wall which is shed during your period. Your hormones regulate how thick or thin that uterine wall is before it is shed. So the thicker the wall, the bigger the clumps are. So as your hormones change, so will these clumps.

Nothing to worry about.