blood tinged mucus discharge after periods

Hi Ladies,

My periods is regular. I am on thyroid hormone tablets(hypo). but no periods prob. But on july month, i got my periods normally. After periods stopped, from the very next day i got blood tinged mucus discharge with back pain. My doc advised to take iron and calcium supplements and after taking it for 4 days all problems stopped. Aug month was fine. Again this month, it stopped on monday(1st sept).from tuesday am getting very light blood tinged mucus discharge while wiping alone. I have moderate back pain as well. i am planning to take the iron and calcium supplements as well. is this something serious? hwo to correct this? i am insane as we are planning to have another baby now.. please throw some light positively, please

blood tinged mucus discharge after periods