We tense and relax all the time and even in class we sometimes do it without purpose. Work on your tension and relaxation adding a purpose to it and note if you learn better to clean yourself. For example if you are standing and tensing the thigh muscles than tense them against a push from the inside or outside and see how the body naturally activates different places and in different manners and sequence. Note to yourself how you feel and change it all over the body. For example tense the neck to keep from bending forward due to a pull as you move your hips to escape and keep moving. Think about the idea behind the activation (tensing up) and the relaxation which is returning to normal. It is not being completely relaxed but aware and in control of the tension which brings freedom of movement in life.

and a personal note, The more you feel the more you feel humble and silly.