I had the same issue, my left rib would hurt so much in the day I had to put small pressure on it to relief the pain (good to check with your gynae if this is ok, I didn’t mention this to my gynae because the pain was on & off). This lasted about 2 months, I don’t have this issue anymore now that baby has gotten bigger (week 32).
Please do see your gynae asap.
Check with your gynae