What Causes Abdominal Pressure While On Enbrel And Methotrexate For Psoriatic Arthritis?

My arthritis doctor regularly has me get blood work done, as I am on Enbrel and methotrexate for my psoriatic arthritis. Yesterday, she said something to do with my liver test was up and I didn t take my methotrexate before the blood work was done because it would ve affected the test. Well, progressively over the past few months, I from time to time, I will just be watching TV or I will wake up in the night with a very uncomfortable pressure around my abdominal and it hurts a little to breath for 5 to 10 minutes. I just try to breath deeply and put pressure against my back with my arm until it goes away. Could my liver be causing these episodes? FYI--my doctor said if the liver test was elivated again in 3 months when I see her, she ll have me get an ultrasound.