I would mention it at your next appt. It's probably just round ligament pain, but if it turns persistent, it could be something else. I know preeclampsia can cause upper right quadrant pain.
i wondered the same thing when i was about 29-30 weeks also, its normal. my Dr said its even more common for the right ribs to hurt more than the left for some reason. bad part, it gets more sore. im 38 weeks tmrw and i ache really badly when shes being a lil terror in there, and always on my right side. ive def got an active lil booger!
Im 32w 3d and last week I had a sharp pain in my ribs also. I saw my ob on Friday & questioned it. She said it's the baby getting bigger and stretching causing some pain. I think if it's a continuous pain then address the issue w/ your ob.