Dragon is back....need support

[Rupali]

So I am back here looking for advice from all of you.
So the biopsy results came back as ER+, PR- and Her2 equivocal. They have sent for FISH test for Her2.
They have started radiation for brain today and are doing whole brain radiation.
Will start tamoxifen tomorrow and decide on chemo or Hercpetin after 4-5 days based on FISH results.

Is this plan ok? What are do's and donts and tips for radiation to keep me going.
Do they give tamoxifen even when I may get back my periods. Last time I remember I had tamoxifen while I was on chemical menopause due to AC+T chemo.

I am worried that if Her2 score comes negative in FISH then what chemo will they put me on as I have already had AC + T 9 years back
Let me know your views