I have had some weird spasms in my left arm. Mostly mild and I notice when I sit w/my forearm on my knee I can feel little tiny spasms start in my upper & lower arm. Raising my arm above my head and massaging it makes it go away. Today I was walking and my left shouler jerked involuntarily for a few seconds. It didn't last long but it scared me. Could this be associated w/the other muscle spasms? It jerked noticeably, not just a little