Left side abdominal pain
associated with lower back pain and below belly button pain can all be caused by bladder or urinary tract/kidney infection
. It is mostly associated with burning during urinating and more often urinating.
Same pain can appear when there is ovarian infection
, uterus infection
or ovarian cyst. It can also be a sign of pregnancy or what is very dangerous ectopic pregnancy. Pregnancy test can by failed, you should repeat it after a week or so.
You should have abdomen ultrasound, blood tests for infection, urine tests and visit gynecologist for examination and ultrasound.