Periods

Hey ladies I've always had very very very abnormal periods. Until recently I never had one. So I was underweight and then my mom put me on bc when I started dating my now husband. I got off the birth control had 1 period then was pregnant. My baby is now 8 mo old but my periods are still strange. My last cycle was about a month ago. But I never stopped spotting from it.... any clue to cause or why this is happening? Thank you for any insight!