Sorry maybe TMI

Normally i have 30 day cycles, and bleed for 6 days, my cycles have always been very regular.This month my period arrived on the day it was due but now i am currently on day 11 of my period now with no signs of it stopping just yet. I have never had a period longer than 6 days.

There has been no changed to my life style, no changes to diet and not currently on contraception as we are ttc. I have called my GP but didnt get anywhere with answers or investigations as to why this is happening, just offered a tablet to take to stop the bleeding.

Any insight on why this is happening is welcomed