33 weeks pregnant having sharp lateral pains on left side abdiman rotating twards center and down into pelvis. Have had some calcium deposits in kidnies and problems with bladder infections during pregnancy otherwise no issues pain is intence than decreices and is very diffficult to walk should I be concerned or what may be causing this?

Any pregnant woman, especially this far along and with other history, should have good communication with her doctor's office. No one online can possibly advise. Certain pains are to be expected while others are not.