Probable Fibroadenoma...with discharge?

New here, and seeking helpful information from those who have experienced a similar situation. I am age 45. I found a breast lump near the nipple about 3 weeks ago, and was surprised that 1) it was there and 2) that I could sort of see it. I've had fluid cysts in my breasts before, and am familiar with what those felt like. They tended to get larger leading up to my monthly period and smaller after. I decided to wait a few days until my cycle and see if there was a change. A few days later after a shower, I checked my breasts again. Out of curiosity, I squeezied the right nipple (not hard), there was a little bit of creamy discharge from only one opening. Since that time I have seen my GP, had a diagnostic mammogram and ultrasound. Turns out the lump that sent me in, is a fluid filled cyst, and there are a total of at least 22 in the right breast.

There was also solid lump I did not feel, and it is roughly the size of a walnut. The radiologist said he is almost sure it is a fibroadenoma. Borders looked smooth and well defined on US. They have recommended follow up with my GP and a core biopsy with a surgeon. My question is: at my age, should I be more concerned about it being something other than a fibroadenoma? When I asked about the discharge, they seemed to shrug it off since it was not spontaneous. Should I push that question harder, or is that a normal thing that I just haven't heard of?

I think I want the lump out, so am also curious as to whether I should even bother with having a core needle biopsy? Is an excisional biopsy a better option than a lumpectomy? I have small breasts, and am concerned.

I guess my most pressing question is from any of you here who are near my age and thought you had a FA when it was really something else?

Thanks for any and all help!