I have a delay of 10 days in my periods. Is there a possibility that this is due to vaccination? Because my vaccination was done just before 2 days to my period date. Also I have history like every time I take any type of tablet for any reason like fever, cold etc. it affects my period date, in addition to that this time I have taken vaccination as well. After vaccination I had taken paracetamol.is it due this as well? I have a doubt that I am pregnant as well because...we didn't use precautions but we were sure to stop at the right time. So I need clarity.