So I Got My Period On October 3rd Till October

So I got my period on October 3rd till October 6th everything seemed fine then on October 15th I got really bad cramps I then bled that night and it stopped the next morning I went to the hospital and the just said it could have been a ruptured cyst but that it s not common for them to bleed but they d leave and to just come back if it happens again but now I m 13 days over due my period which should have been on the 1st November.. any idea as too would a ruptured cyst cause if it even was a ruptured cyst because they never done any check ups or ultrasound