@alic First let's translate 7mm - it is just over 1/4". Here is what a pulmonologist said to me - "Imagine trying to guide a needle to a moving target smaller than your baby toenail, pierce it without going all the way through it, and extract cells from it to test."
In general, where there is a minimal risk of cancer, most doctors practice watch and wait on nodules smaller than 15-20mm.

It might help you to know that small nodules have about a 5% chance of being malignant, and one of the key factors evaluated during watch and wait is whether the nodule grows, and how fast. With your history as a non-smoker with asthma and repeated infections, as well as other nodules that have not grown over time, your doctor probably fells your risk is even lower.

I hope all of this information eases your mind as you watch and wait. In the meanwhile, one thing you can do to help your lungs is to keep your asthma well-controlled so additional problems don't occur.