What happens to you after performing a spell?

Generally, you become jittery because of the excess energy that is in your body. Once you ground that extra energy, you become hungry and tired. It is best to eat after preforming a spell, to replenish your own energy.

If you are talking about "Divine Punishment", you are only "punished" if you believe you should be. In my opinion, you shouldn't be doing a spell if you are afraid of DP.