My cycle is about 50 days. I was suppose to o on the 16 but i think I did on the 13th I had o pains. Bd 4days before then. And then on 15. Shouldn't start till the 1st if dec. And I am spotting. So either imolantation or period starting early. So if was implatation spotting how soon after it starts should i be able to get a positive if I was.