Tension

We all have areas of our body that are tense while playing. Tension leads to poor tone (when this tension is from the neck up), slower playing (tense muscles are slow muscles) and fatigue (upper back, neck and tongue). It should be a goal of yours to practice and perform as relaxed as possible (body and mind). Put a jam track CD on and play through the entire CD. You could also make a playlist of the songs you've learned so far and play through all of them in one sitting. After this long playing session make note of where you're getting fatigued... these are the areas of your body you need to work on relaxing.