Photodynamic Therapy for Acne - Carried out Correctly? No Reaction/response, No Redness and Peeling, is This Normal?

Hello, I have had photodynamic therapy performed this week. The procedure was carried out as follows:45 minutes of ALA being applied to face in 5 minute intervals.I saw that it was a small bottle. Not all the bottle was used, in fact very little ammount. Blue Light(ipl?) was used on face, didn't hurt badly, just felt hot. This didn't last very long and was performed in less than 5 mins.I was not red AT ALL after the treatment. Still no redness or peeling,disheartened as to whether it worked.