9 mm lung nodule - new in last few years

I went for an xray a few years back and the dr found a  5mm lung nodule on my right lung.   I was sent to a specialist and after a ctscan, found that the nodule was calcified and something not to worry about.

Last month while going for an abdominal scan, they found a 9 mm nodule on my left lower lung that was not there 3 years ago and based on the "color" is not calcified.   The issue is that the slices of the ctscan make it difficult to determine if it is indeed a lung nodule or a cyst or something like hanging off the diaphragm.     The next steps is to wait for 6 months and rescan.  6 months is a very long time worrying.  

I tried to look up what a diaphragm cyst or hernia and can't find anything I can understand - all results are in "doctor speak".   Can you explain what this could be?