question: Hi I am 22 wks pregnant and I just found out that I have crystals in my urine . I am in constant pain in my lower back on both side and in the middle. At times the pain radiates to my butt. According to the dr they want to rule out kidney stones . If it that I have kidney stones what is done for that? Also I am not gaining much weight. I will gain 2 lbs and then lose the 2 I have gained. At times I have no appetite at all. I eat at least 2 meals a day but never finishing it because I am full fast. Any suggestion on what that can be and why. I had 2 prior pregnancies that went fine. One of the pregnancies I went preterm at 7 months but they stopped the contractions. Any help would be appreciated.