Hello there. I know it's easier said than done but please try not to stress yourself as you will make your symptoms worse even if they're minimal or non-existent. My dad was diagnosed with nsclc on February 22, 2017 and passed away on July 1, 2017. He was one month shy of 79 years old and hadn't smoked since his 20s however let me remind you that everyone is different. Unfortunately for my dad, he was diagnosed at Stage 4 when doctors discovered a 7cm tumor in his right lung. The cancer had already spread to his chest wall, lymph nodes and liver. As a result, we decided not to pursue treatment as dad and our family chose quality over quantity. In other words, we chose to have a decent few months left than an extended miserable year. The fact that you've been surviving since 2015 is such a blessing! There are lung cancer survivors out there so keep your faith and trust in the Lord. Pray for the best results. I will say a prayer for you and your family as well.