I'm 14w1d and have had rib pains on both sides almost like a runner's stitch or like I worked out my core too hard. I haven't done anything so definitely not the case. I can't see it being round ligament pain because I have had those sharp pains down lower when I move too fast or roll over laying down. The only thing I can think of is that I switched to one of the c shape pregnancy pillows three nights ago because I was struggling to stay asleep at night and that seemed to help. I'm petite (124 lbs, 5'1") so maybe it's just being smaller and feeling it more? I haven't been throwing up or sick, so wouldn't be from that either.