SPD vs Sciatica

Anyone experiencing lower back pain? I can’t decide if mine is related to SPD or my sciatic nerve.

It hurts just above my right butt cheek and doesn’t shoot down either leg. It’s usually most apparent when I transfer my weight to one side while sitting.

I also get the feeling like a I need to stretch my groin area while walking after a long period of not moving.

I walk a lot during the day and run 3-6 miles on the weekend.

Anyone else dealing with this? If so, have you found remedies to curtail the pain?