Is Subpleural Nodule In Posterior Basilar Segment Of Lower Lobe On Leg A Cause For Concern?

Hi. I was hit by a car (I was a pedestrian) on Jan 9th and have had 4 trips to ER as I have no health insurance. I don t want to keep going to the ER, but am not sure if I should. I have had crampy type pain under right rib since accident and last night I had sharp stabbing pains for couple of hours. I don t know if to go back to ER. CT w/out contrast showed nothing significant in the area, though a 3.4 mm diameter subpleural nodule in the posterior basilar segment of the left lower lobe was found. I want to add that I had a heart attack in 2007, but no evidence of recent cardiac event following hit.