In Constant pain

Im not to sure if this pain will ever end. At times it doesn't feel like it will. First it feels like a burning sensation then follows by a sharp pain on my lower right side of my stomach. All i can do is lie still and not move till it does pass. This at times can take anywhere from an hour to 3 hours. This all ends with my lower back striking painfully. This has been going on for the last 3 weeks. I have seen a doctor and she doesn't know what to tell me when it comes to what is causing my pain.  I recently went for an ultra sound on monday morning. I go to get those results on Wednesday. I am only 23 years old and my life is being taken over by this pain. It is stopping me from enjoying my life with my son and my boyfriend. 

If anyone can give me any insight to this I am more then happy to hear anything.