Unexpected bleeding

So I had my period on the 12 of this month and on my last day of my period I had unprotected sex. So obviously I took the plan b the next day around the evening. I recently just experienced bleeding within the past two days ? Is this a normal side effect ?

I also did change my job and it requires more labor than my previous employment. Would that also be an effect as to why I am experiencing vaginal bleeding after passing my Menstrual cycle ?