I have my Oncologist puzzled - Oestrogen has increase post menopause

I always find it really strange that doctors can have differing opinions. I was  told that blood tests for menopause are often incorrect. Seeing that your bloods are inconsistent the drs choice for Tamoxifen is wise as it can be a pre/peri/post menopausal drug. Maybe your body is just working it all out after the trauma of the surgery. Our bodies are complex beings