Reaction to the Levulan Treatment for DSAP on Arms

I had a Levulan treatment for Disseminated Superficial Actinic Porokeratosis (DSAP) on both my arms, and there was no reaction at all - not on the lesions, and not on any other part of my arms. Do you think that the treatment was done correctly? When I asked that question, no one at the Dr.'s office would answer me. If it will work done correctly, I would like to try it again. If not, then there is no point. Thanks.