I had a friend who was a black belt karate instructor sit in on one of my classes. He said to me "I can see your frustrations with the whole thing, but you seem so tense around your Sensei and when he walks away, you're a lot more relaxed. Just relax and let the process take over. Don't think about things so much!" I believe, and perhaps know, that whenever Sensei is around, I just freeze and mess up because I'm afraid he's just going to tell me I'm doing something wrong again. In other words, I seem to be conditioned to be afraid of him. I'm not this way around the other teachers.
you have accidentally stumbled upon a less well-know power of the sensei. it called the dork. it's similar to the Jedi's force, but it is more insidious. whenever you come under the influence of the sensei's dork power, you are it! you would feel like a dork, act like a dork, and move like a dork. the obvious way to deal such dorky power is not to be in the presence of the sensei. however, the obvious way have been tried and failed. many students have paid the price for failure with their lives and dues. it was horrible to witness. their bodies littered the facebook landscape, bemoaning the beauty of aikido in their dying breath. the best way to deal with such power is to not shy way from it, but embrace it (it kinda of scary to embrace the dark side but you will get use to it) by become even more dorky than normal when you are near the sensei to the point that the sensei walks away in disgust, which is when you know that the method is working. good luck and may the dork be with you! live long and prosper in dorkiness!