16 weeks pregnant with pain

Hello. I am currently 16 weeks pregnant and I have been having pain on my right side, it started when I was 10 weeks. They have done all types of tests and have found nothing since then and the baby is good. They say they are not sure what it is, it could be kidney stones or just my organs or ligaments moving and stretching. At this point I am so confused and don't know what to believe it is. I am more worried about it since I am pregnant because I want the baby to be good. Has anyone else had this or something similar and how did it turn out.