I used to use a mild semi-western grip. Now it's more of a true semi western with the whole base knuckle of my index finger on bevel 4. As a result my stance is a little more open. I was hitting too flat before, now I have the option for more spin which is what I need for consistency. However I've noticed that that the deltoid on my hitting arm is now very sore after playing. Is this to be expected when hitting with a more open stance and a grip closer to western? Or is my technique just bad and I'm hurting myself?