Complex cyst question

Hello,

I have had a complex cyst in my left kidney that has been watched for about 4 years, my last MRI was October of last year, so I'm due for another scan within the next few months.

The MRI report from last year stated: Multilobulated 4.5 x 3.6 cm cyst in the upper pole left kidney with a couple of thin internal septations. No solid nodularity. No thickened septations. Finding is stable in size when compared to previous.

 The kidney specialist that I saw at Northwestern said that the cyst is actually "in" my kidney, not "on" it, which makes removal more difficult and also he felt that it looked benign, but should be watched.  I did get a second opinion at the Mayo Clinic in Minnesota and they agreed and even said that this time I can do surveillance with ultrasound instead of MRI.  

I had a prophylactic double mastectomy last year due to genetics, and a bunch of pre-cancerous cells were found that never showed on any screenings.  I have PALB2, ATM and PTEN mutations, and I believe it's the PALB2 that raises my risk for renal cancer.  

I thought I had a bladder infection starting a few days ago, feeling some urgency, burning and crampy pain on the left side of my back that radiates at times to my groin.  I went to my gynecologist who did a urinalysis and put me on antibiotics to be safe, and she just called and said my urine was negative for everything, and to stop taking the antibiotics.  She is aware of the kidney cyst and said to call my internal med doctor to order a scan to be sure all is ok.  

His office is closed today (of course), and I'm just trying to not go to a bad place with my anxiety!  Since there was no blood in my urine, that is a good sign, hopefully?  And a cyst that size of mine really shouldn't cause pain?