3mm lung nodule-should I be concerned?

My mom was recently diagnosed with Stage IV lung cancer, so I decided to get a lung screening at the hospital myself.  I have never ever smoked, but I am overweight.  The results came back stating that I have a 3mm nodule in the left upper lobe, pleural-based, as well as some other calficied nodules.  They said that it was of questionable significance but that the CT should be repeated in 6 months.  Has anyone began their journey thru this with a similar diagnosis?  Any info, good or bad, would be appreciated.

I would ask the doctor for a PET scan.  They did not find mine either until I had one and that is because my doctor forced the issue with insurance.  Thank God, I was in surgery with 2 weeks. 

Doc forced the issue because my dad had lung cancer and died from it.