Period!!! Help I'm starting to get worried...

my periods have been off since summer time it did an vaginal ultrasound a few months back they said my uterus was thicken they talked about doing a D&C; they are sending me to an OB doctor but literally I've been bleeding since summer on and off been having a lot of blood clots I'm just getting sick of blooding has anymore had this happen to them??? I'm 40 years old I ask my Dr if I could be going through menopause and she said No and I'm wondering if it's not that then what could it be then??

one other thing I forgot to add me and my boyfriend been trying to have a baby since summer to that's when my periods have been acting up