Hello @layla7511, When I had my first occurrence of PMR, it was worse in the morning but gradually got better during the day and got progressively worse and the pain stayed with me all day/night until I met with a rheumatologist and was diagnosed then put on prednisone.

Excerpt from Mayo Clinic Polymyalgia rheumatica - Symptoms and causes:
"Aches or pain in your shoulders. Aches or pain in your neck, upper arms, buttocks, hips or thighs. Stiffness in affected areas, particularly in the morning or after being inactive for a time. Limited range of motion in affected areas. Pain or stiffness in your wrists, elbows or knees." -- https://www.mayoclinic.org/diseases-conditions/polymyalgia-rheumatica/symptoms-causes/syc-20376539

You mentioned that you worry that the pain is not caused by PMR. Normally when you are diagnosed the doctor or rheumatologist will prescribe prednisone as the drug of choice and it gets rid of the symptoms pretty quick. Did your rheumatologist prescribe any medications like prednisone for you?