D-iii rhp

I pitch at the Division III level and I am looking to add velocity to my fastball by improving my mechanics. I think they are sound and repeatable already but I do not think I am getting all the power that is available from my frame. Also, I tend to get sore in the bicep/upper forearm region after I throw so lately I have been worrying that perhaps my elbow is dropping. The video in which I am wearing red is a video from this summer when I feel I was at my best in terms of mechanics and velocity. I developed left groin and hip flexor tendinitis and and took the rest of the summer off. I am now back to throwing but I don’t feel as good as I was. The video of me in the gray is from a few days ago, and obviously I get a little frustrated missing a lot of my spots. Any thoughts are appreciated.

The camera angle of you in the red is a little different so I cant tell if your stepping to the same spot but of you in the gray your not stepping straight towards the plate. your closing yourself off and then you have to fight through that to get to the plate. Stay through to the plate and stay in the weight room, the velo will come