2nd period postpartum help!

Jade
Long story short,  my first period postpartum was maybe eight weeks after I had the baby and maybe a little further along and actually. But I bled for about 45 days and it was just like my average flow pre-pregnancy. Now 28 days later I get my second period and think nothing of it, until now on the seventh day I'm still bleeding! Like a lot, bright red still and this morning I woke up and I'm a little tender in my uterus... has this happened to anyone? A period this long?