What Causes Abdominal And Back Pain Post Alcohol Intake?

Hey ive noticed in the last 2 months I have been drinkin a little more than usual nd ive been bruising easier. Nd the last 3 drinks (alcoholic) I have ended up with pain on the left hand side front abdomin nd my back have been hurting. Almost like a stitch some times it doubles me over... wat could this b?