Metastatic breast cancer in my liver

Hello, This is my first time posting here. I was diagnosed with stage 2 invasive breast cancer in 2017, I had a lumpectomy and 3 lymph nodes removed, I was told there were no signs of cancer in the lymph nodes so only need radiation. I had a bad reaction to the radiotherapy, but with 6 weeks of steroids recovered from that. They then said they could see some lesions on my liver but after 3 months and another MRI it was decided this was not cancer. I was given Letrazole, which I was told I would need to take for 4 years, this gave me very painful joints so this was changed to Tamoxofen, the only side effect I got from Tamoxofen were hot flushes which were quite intense but manageable. 4 years later and after a CT scan for digestive problems, namely very acid stomach, I was diagnosed with a large tumour in my liver and further smaller tumours. I had a bit of a delay in seeing the consultant but was again put on Letrozole and Palbociclib I have now been taking them for just over 2 months, I am still getting very bad hot flushes but so far my joints are ok - I do try to exercise regularly and that does seem to help. Unfortunately with the Palbociclib by neutrophils (white blood cells) each month have gone down to .50 so the first month I had to wait two weeks before I could start the next month, the dose was lowered to 100 mg but the same thing has happened again this month .50 again. I am hoping I will be able to carry on with the 100 mg this month - has anyone else had this problem? I am quite worried - I have just had my first CT scan since starting the medication and feeling quite nervous to see if the medication is working. I would love to hear from anyone with the same sort of problems - thank you x