Okay, so the last time i had sex was about a month ago and my period was a little late but I finally got it on Dec. 22nd. The strange thing is that it's really light, much lighter than usual. When i use the restroom, the toilet water is red but when i wipe there's barely any blood. There's only a few drops of blood on my pad as well. I know implantation bleeding occurs almost a week before your actual period, but mine was a couple days late and my period is still light. So, can implantation bleeding occur much later or is this something else?