experience with implantation bleeding??

has anyone had experience with implantation bleeding? I have had 3 babies and never experienced this. I'm curious how soon after intercourse does this bleeding occur? is it during intercourse or a few days later? ... the reason I'm asking is because the other day I had intercourse and had some slight spotting immediately afterwards. it didn't last long though. I thought maybe it was because it had been a while since the last time we had intercourse but just curious what implantation bleeding is typically like.