That side view is way too far back. Take your video camera and bring it a lot closer, say about 15 feet away from you.
It's not all that important to see the entire pitching cycle from beginning to end. The key viewing that I'm interested in is the part where you bring the pitching arm from the breaking of the hands - to the high cocked position - to the pitching arm's forward motion with your stride.
Again, try and put your camera about 15 feet from you and focus that camera on the side, then in back of you.
A few questions for you:
- is that pain only after you've completed a full presence on the mound?
- is that pain experienced at a certain point during your presence on the mound... like after the second inning of work?
- is that pain only after pitching a certain series of pitches?
- is that pain only after pitching a certain combination of pitches / like four seam, then a slider, then another slider, then a four seam, etc. ?
- are you in the process of learning a new pitch? The reason for me asking that is because it's not all that unusual to experience discomfort and sometimes pain in the shoulder and arm when learning the split finger and fork ball. I've had pitchers well into their late 20's experience discomfort and even some pain - especially with the split finger pitch.
- is that pain accompanied by any stiffness in the back of the neck?
- do you play any other sport(s) that require arm action with your pitching arm?
- do you take a hot shower, rub down with liniment, and rest at least three (3) days after an appearance?
- and finally, do you pitch only heat (fastballs)?