Poor posture can put strain on nerves which can cause pain. been there, still there and i wish i had listened to my teacher ten years go.
But maybe all of this has another reason:Mindlessly repeating "note sets" is a very easy and effective way to get an injury, because you shut down creative thinking and listening. Your mind wanders away and you end up not paying attention to the sound/naturalness of what you are doing. So find some pieces with these things you want to work on. Working on musical stuff will always be more interesting, so you it will be much easier to catch bad movements. If you are looking for suggestions, write exactly what technique you were looking for and I will search something for you