Lung function test, and x-ray?

I had a lung function test, and was just under the limit, i discussed it with my doctor and showed him the graft, he said it was normal,he listened to my lungs at the back, and told me to go for an x-ray, on the slip of paper he gave me, it said, slight crackle in lower left lobe. I had the x-ray done, and now i have been told to make an appointment to see my gp, and to say the least it is worrying me.