I have been having this dull ache in my left side lower back hip area at night time. It has turned into a sharp stabbing pain. What could it be?

See below. There are lot of possibilities like a urinary tract infection or kidney infection, kidney stone, muscle sprain, strain or spasms, pelvic disease like endometriosis or pelvic inflammatory disease, spondylosis, disk injury or spinal fracture, inflammatory bowel disease, etc. See you doctor soon.