Any Ideas?

Brittany • Momma to a spunk 4yo boy (6/11/12) and a new little girl (5/25/16)
I'm 19 dpo and there is no sign of AF except for some random times of major cramping. I have become quite moody and tearful over little things. I took a hpt a week ago and AF is over a week late. About 4 dpo I had a few days of very light spotting. I am so confused about what my body is doing!