Get rid of the creatine is what I suggest. At your age (at any age, but especially the older you get), creatine is not good for your kidneys, it dehydrates you because it takes water from other parts of your body and stores it in your muscle mass. That's why people who take creatine may have muscles that appear bigger, although it is only an illusion, as the extra 'muscle mass' is simply water.
Also, you mentioned after your workout, that a few hours after, your muscles return to normal and are soft. That's likely the creatine.