Ok so is it just as likely to experience symptoms from a 2.6cm (or smaller) lung nodule as it is from a lung mass?

Same thing: Lung nodule, lung mass, spot, tumor, lesion ... All mean the same thing.

Variable: Most small masses, nodules, lesions of that size are asymptomatic! the incidental finding is good luck. Depending on exact location, bronchoscopy may define the cause most will be removed. Some will biopsy first, but the thoracic surgeon will guide this with you.