Any pain in your abdomen should not be ignored. Women may experience pain or heaviness in the lower abdomen due to many reasons. You may be experiencing pain because of ectopic pregnancy, miscarriage, menstruation, pelvic inflammatory disease, fibroids, or endometriosis. Since you can better describe the frequency and intensity of the pain in your lower abdomen, it is best if you consult your doctor so that he can diagnose the problem and treat you before further complications arise.