Humiliated by security staff at the door

at about 13:00 ish on Tuesday the 28th Nov 2017 I walked into your Canal walk store, quickly just to replenish my make up and go. It was really a quick in and out as I was rushing to get back to work. Paid my stuff, put it in my handbag and walked out. As I walked out the door the alarm went off, obviously that meant i had to come back and whatever i had to the security lady at the door, and in this case it was my handbag. I didn't feel comfortable doing that, so i took out the stuff i bought and gave it to her to pass it through and see if it beeped but it didnt...then I gave her my handbag to pass it through, she did and it didn't beep, then we put the stuff back into the bag and passed it through, then it beeped again. Now i was starting to get annoyed, as this lady started scratching in my handbag, going through my stuff to see whats causing the alarm to go off. I'm already feeling humiliated and embarrassed by this whole exercise as everyone including the people that were walking by suddenly stopped to watch. This security woman called her her supervisor who also just stood there and watched her as she was turning my handbag upside down to look the for stuff I supposedly have "******" to give the beeping sound at the door. She obviously found nothing even after she opened up the boxes of the make up I purchased. Never have I ever been that humiliated at a store before...people were literally starring as she was causing a scene scratching in my handbag. I wanted to take it up with the store manager there and then but I was in a hurry as I was running late already for work, especially after all this drama now. after about 5 mins, I was given my handbag with the goods I bought to walk out...which didn't beep this time around. Now my issue is, if you/security knows that your systems are malfunctioning like that, why put us through such humiliation knowing very well that it could be the system's malfunction. I knew for a fact that I didn't ***** anything and if anything was causing the sound must have been something in the stuff I bought, hence I handed that to them. When that didn't beep...and my handbag alone didn't beep....I didn't see the need for the lady to now still scratch in my handbag, invading my personal space like that! I was very upset and angry and still am about this...will make me think twice before I ever visit your store again!