I am a female. i have a constant heavy feeling in lower abdomen, sharp pain on the right side during sex and lower back pain?

Right SIJ disorder: ? why right low back pain, "heavy lower abdomen feeling" & dyspaerunia. Unifying disorder might be right sacroiliac joint hypermobility disorder, which can be associated with IBS and/or refer pain to the mid-pelvis. During sex in the missionary position, the femur leverages this joint arousing subluxation and pain generation.