Transvaginal Ultrasound 5mm mass, no bloodflow. 1.1cm endometrium; 1.5cm probable hemorrhagic ovarian cyst. Should I worry? Very heavy menses, IV Fe.

Sono not worrisome. The findings on your transvaginal sonogram do not seem to be cause for alarm but unfortunately they do not explain why you have "very heavy menses" and need IV Fe...which are "causes to worry". It would be good to consult a hematologist to rule out a blood coagulation disorder and a Reproductive Endocrinologist to find out why you may or may not be ovulating regularly and why you bleed heavily.