Muscle Twitch

Wasn’t sure what forum to put this in, I realize it’s not an injury. For the past week or so I have had a constant twitch in my right front delt. When I look at it in the mirror, I can see the muscle quickly and involuntarily contract and relax. It happens about 5 or 6 times a minute. Any ideas what the reason for this might be? It isn’t painful, but it is getting pretty annoying.