Implantion Bleeding

Is it possible to implant bleed the day you’re supposed to start your period? I still have sore boobs (started the 16th) and I’ve been super tired lately. Today I was supposed to start my period and I have had light cramping this morning around 6 am but it’s currently almost 5 pm and i used the bathroom and only saw a small faint light pink spot on tp. Normally my period would’ve fully started with heavy cramping and would’ve been a dark red by now. 🥴