Lately after playing my left (bridge hand side) shoulder aches, it usually last for a while but goes away by morning. I've done stretching about a hour before swinging the cue and I still get slight pain later. I play about 2hrs a day during the week and 2 4hr sets on sat and Sunday one early and one late afternoon so I don't think it's from over play. The discomfort feels like I pitched a baseball game! Is this normal? I'm also 47yrs old if that matters.