Talk to Gastroenterologist on Pain In The Lower Left Back.

Asalam-O-Alaikum.

I am having a pain in my lower left side of the back from 1 week. I do not know if the pain is in muscle or some bone. Whenever I go into the position of bowing or any other forward upper body stretch, the pain is felt in the mentioned area and the little bit of pain on the left side of abdomen too. My friend suggested me an exercise (Active Hip Opener). Whenever I do that exercise, the pain temporarily goes away like 15 to 20 seconds then it again starts to hurt. Notice that the pain is felt only when I go into the position like bowing or any other forward upper body movement.

I want to know that should I check in with a doctor and who is the expert for this kind of issues, or should I continue doing the exercise until the pain is completely gone.

Hoping for satisfying answers from experts.