Pain in lower abdomen

Just wanted to know if anyone has experienced this before. Last night I was getting up out of my recliner and I felt an extremely sharp pain in my lower right abdomen and it has been constant ever since. It's only been about 12 hours, but it hurts to stand straight up and it hurts to walk. My husband thinks I may have just pulled a muscle in my abdomen or we think it may be round ligament pain, but from what I have read, it isn't supposed to be constant or be so painful that you can't stand or walk at times. Just wanted to see what others thought or had experienced since this is my first pregnancy. I have an appointment for an ultrasound and a prenatal exam on Friday, so I figured I would mention it then. Any advice would be greatly appreciated !!