15 Early Signs You Might Be Pregnant
Spotting

Spotting can be mistaken for a period, but it has a couple of distinct differences. If what you assume to be menstrual blood is much lighter than normal and a few days earlier than usual, it could actually be a side effect of the sperm's implantation. When the fertilized egg attaches to the uterine wall, it can sometimes cause a small amount of blood to be shed. Thus, spotting.