What would cause pain in the lower stomach and pelvis area? Its like a sharp constant pain..

Many causes. I think what you are trying to say is lower abdomen instead of lower stomach. The two main systems that may be at play here are your gastrointestinal and genitourinary system. You also have to consider other associated symptoms such as relation to bowel or bladder function. Other factors could be arthritic condition of the pelvic bone. Have yourself thoroughly examined by your physician.