CT scan find

Hi

I had a CT scan to check my lungs and they've found a 1cm mass in my breast. Not exactly what I went into hospital for today. 

Apparently it's on the edge of the image, but I don't know if that means the side of my breast or not as I don't know how far across my body they scanned, and as my breasts fall to the side of my body when I lie flat I guess that it could mean the centre of my breast tissue.

I can't feel or see any lumps. No pain beyond normal period related sensitivity.

I've been referred to the breast clinic next week for a mam and ultrasound.

I'm stunned and scared and frustrated. I like to know specifica but no one can tell me any more. 

Anyone had any experience with surprise CT scan findings?

Thanks