I had a ct scan in may of 2011 showed 1.2 mm cyst on liver , posterier, superior. Also 4 mm nodule medial & posterier left upper lobe. Now I for past two weeks severe, gnawing pain lower right rib radiating over all of right side. Frequent need to urinate, and severe lower back pain at times. Dr has tested blood for liver, all clear. Dr ordered new ct scan of chest. Do I need to go to Ed if pain gets worse?