I was just told the same thing about a 6 mm nodule. I am going to a pulmonologist in June. I don't even want to think the C word.
I would definitely speak to a pulmonologist about it. I had a routine chest x-ray and they found a 12mm x 16mm nodule on my lung back in March. It turned out to be histoplasmosis, but it looked for all the world like cancer on the CT scan and also on the PET scan I had done. I have a family history of lung cancer, so they took no chances and did surgery to remove it. Then I had to be on the drug itraconazole for three months to make sure it didn't spread. Today I'm pretty much fine.
In your case, because it is rather small, they may just opt to watch it and see if it grows. Keep us posted on what they tell you.