Cystic breast changes? Waiting for biopsy results

Hi all

I'm a bit of a nervous wreck today after attending a follow-up appointment this morning, thinking the same thing would be said as it was at my initial appointment 5 weeks ago - that the lumps I found in my right breast are due to cystic change. I had an ultrasound to confirm this and felt really reasurred that this was all perfectly normal. (In the weeks before my appointment I'd noticed my right breast was a little swollen and then I noticed I could feel little lumps. I no longer have swelling but the non-painful lumps remain.)

I went back today and had another examination. The consultant spent longer on the examination today, and then said he wanted to take a sample to send to the lab - he inserted a fine needle for this. He did say that it was more for reasurrance and I shouldn't lose sleep over it, but I can't help but worry that he's noticed a change and has cause for concern.

I'm trying to make myself feel better by looking into whether there's a link between the Mirena IUD (which I have) and cystic changes in the breast which could explain it, but I'm not sure there's a link there. Hopefully their initial suggestion still stands, which I believe isn't uncommon for my age (I'm 34).

I'm trying to take his advice and not worry too much, but it's really hard and I'm wondering if this is something they say to help relieve anxiety when waiting for results. 

Thanks for reading my rambling thoughts!