I don't know why I don't remember this...it's not like this is my first baby!

So I got AF back at 6M PP. I was shocked because she was 100% BF at that time (well very little solids if any) and still nursing overnight. It was a full AF - heavy and lasted like 5 days. Well that was 40 days ago! I have been waiting and waiting and waiting for her to return. Is it normal for AF to be messed up for the first few cycles? I have had long cycles but not 40 days....I am dying here!