Hi E.,
Congratulations on your second child! Your post brought back memories because I experienced the same symptoms after the birth of my second child, which I did not go through after the birth of my first.
Even though I was nursing I still experienced bleeding; I found out that breastfeeding doesn't guarantee no periods. I also found out that the extreme pain I experienced was my uterus shrinking back to prepregnancy size. I did not feel this pain after my first child so it was scary to me, AND it seemed to come on during and just after nursing. I then was told that the letting down of milk to feed the baby also stimulates the uterus to help shrink
it. It's all about the hormones and understanding this can help relieve the stress you have by worrying. Having said this please do check with your doctor to rule anything else out.
Good luck with your newborn and your growing family!
All the best,
S. C.
Maternal Dance