How possible it is to have implantation bleeding 4 days after intercourse? and how does it feel and look like?

Implantation bleeding…: Four days is a bit early for implantation bleeding but not impossible. We see it sometimes when we put in advanced embryos. Normally implantation bleeding wouldn't beef until 7 to 10 days after conception at the very earliest. However, biology is a wide bell curve of reality. Having said that… it's always good to make sure there aren't other issues at hand. A good ultrasound is always a fine idea :-).