Go to a specialist if you can afford it. Along with muscle strain, you could have ligament, tendon or cartilage damage.
I've always had issued with my elbows because of 100 or so impacts from skateboarding. I recently had an MRI done and they found at least 4 floating chips of bone in there.
I doubt you have that but it is possible. Pretty painful when the chips get lodged between stuff.
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