Hi, I'm female, 28, and was diagnosed with stage 1 er+ breast cancer in July 2020, had lumpectomy & sentinel lymph node biopsy, followed by radiotherapy and tamoxifen which I started in august.

I had bad night sweats and hot flashes when I first started taking the tamoxifen, which thankfully subsided after 2 months, but then started getting lower back pain and lower abdominal pain at the end of October, and from mid December I've had a change in bowel habits and some bleeding when passing a stool (I've not changed my diet, I eat healthily and exercise regularly). I went to my gp about the change and she said a fissure was causing the bleeding, and to try stool softeners when I'm finding it difficult. I'm still struggling with my bowel movements, lower back & lower abdominal pain, and can now feel a small hard lump on the lower right side of my abdomen.

Is this just awful side effects I'm experiencing from the tamoxifen?