Left flank pain near kidney. Reduces.

I got an extremely bad pricking pain on my left side last week. I wasn't able to bend forward or backward and even sneezing caused extreme pain(stabbing pain) but next day it went down. A day later it came back with the same severety. After consulting with a doctor I was told its a muscle spasm. But it doesn't feel like a muscle pain. Abdominal ultrasound ruled out chances of any issues with kidney, pancreas and stomach. The pain is not there anymore. Now when I wake up in the morning if I bend my neck down and slightly to the left I get a pricking/stabbing pain on the left lower back somewhere bear the kidney. It feels more international. Doesn't feel superficial like a muscle issue. If I tighter my abdominal muscles and then bend my neck I don't feel the pain. In the later stages if the day the pain in bending my neck reduces.