Spotting and Back Pain: Menopause Complications?

Hi. I've gone back and forth on posting here all week. I went through menopause at 34. I'm now 39. Had spotting for the 1st time in years in September. My lining was 8, but endometrial biopsy came back normal. Last weekend, started spotting again with cramps and awful lower back pain and heavier spotting than before. I have a TVU today and doctor said if lining is more than 4, a D&C is next. Just hoping to get feedback/thoughts/other people's experiences because I'm not sure what to make of all this. Oh, and my functional medicine doctor started me on estrogen in January and my gyn was very upset because apparently that accelerates issues, which I did not know. Thank you in advance.