Had Spinal Fusion C4-5 Two Years Ago. Pain/numbness Was On

Had spinal fusion c4-5 two years ago. Pain/numbness was on right side. Have had hip flexor/sciatic pain for 6 months. MRI inconclusive except for slight tendonitis. PT/massage/rest/stretching have not helped. Now have the same pain/numbness I had through neck,shoulder/arm but on left side. My question is: How do I know if I have true muscle or bone issues or is this menopause related? I am a healthy white female age 54. Height is 5'6'', weight is 125. Until 6 months ago I was running 25 miles a week, doing half marathons, strength training, etc. Now I can't even go for a walk without hip/back issue hurting and left shoulder, neck, arm can't find comfortable position. I want my life back!