I'm 6 weeks+ pp and bled for 3-4 weeks after birth then just occasional light spotting and nothing for week or so. Now I'm downright bleeding again today. It's light, but why? I don't remember bleeding this long with my other pregnancies. Anyone else? I have an OB appt next week so will make sure all is normal then. I'm sure it is and I'm sure I'm not fertile yet. TThat usually happens at about 6-9 months pp for me even with nursing and pumping.
Usually postpartum bleeding is a sign that you are doing too much. Judging by the ages of your kids im guessing you cant really take too much time off! If the blood is light colored, and not the flow of a regular period - you have probably just overdone it a bit - walking too much, lifting too much etc...
after i had the twins last year, i started bleeding again after about two months... it started very light and over the course of a few weeks became heavier and heavier. for some reason i didn't make an appointment to get it checked out for several weeks but when finally did they the most likely cause seemed to be hormonal... i think they did blood work to rule out a thyroid problem and i did get scheduled for an ultrasound the following day to rule out any retained parts.... unfortunately for me it turned out to be retained placenta :(( can you still feel your uterus above your pubic bone?
in any case, i think those are the most likely causes for bleeding unrelated to your cycle... hopefully it's just a funky cycle or a hormonal thing!