Spleen enlargement. The emergency room?

During a routine ultrasound for my pregnancy yesterday, the tech took measurements of my kidneys, spleen, and gallbladder due to my pain. Everything was noted to be normal except my spleen being 'slightly' enlarged to 14.1 cm (i have a visible lump right below the ribs). I have been experiencing pain on the left side of my abdomen, from my ribs to no lower than my belly button area for about a week. I was seen by my OBGYN who claimed it was one of my babies flipping from breech to vertex. However the pain has not gone away, and the baby hasn't changed positions again. It hurts more to lay on that side and I have been feeling a gurgling sensation every now and then. The pain is a relatively constant ache but not bad enough to make me cry.  Should I be concerned and what can I do to help the pain? When should I go to the Emergency room?