My period is a day late & very light, is this a sign of pregnancy?

My period was a day late & now when I just woke up I saw a few drops of red blood in the toilet. I looked online & some people say it's implantation bleeding when this occurs, which is a sign of pregnancy. However, I've heard that implantation bleeding is very rare. So idk what this is. Has this ever happened to anyone & ended up pregnant?