Can a person's body react against and have negative side affects from long term hypnotism?

I've been doing a self hypnosis weight loss tape for the past couple of weeks. The tape takes you through the steps to get into the relaxed state and then talks about eating less and how good it feels to lose weight and even goes into some situations like shopping for food. While I do notice that I eat less and eat better, I also feel really depressed and it seems like my body aches in my joints. Granted I realize that my body could be adjusting to the change in diet but I also wonder if for some reason my subconscious might be "fighting back" for lack of a better term. That maybe there is a deeper coping method with the food and my mind doesn't really want to deal with it. Does that make sense?