Name changed for obvious reasons
Please try not to worry too much about this.
I also shoplifted at his age, only once, and a relatively ridiculous white nail varnish, but nevertheless wrong.
It was an impulsive act and if you had asked me then why I did it I couldn’t have answered. Looking back I think it was a reaction to overwhelming teenage angst, a desire to keep up with my peer group and a feeling that I just didn’t belong.
I have never stolen anything since, had a successful career in Finance and even spent several years investigating Financial fraud.
The latter taught me that people don’t always steal because of financial need. Some do, but emotional factors are often very instrumental.
My advice would be to approach the situation through talking to your DS and listening. You may not get answers immediately, but are much more likely too if you approach it from this stance. Your DS will know you are shocked and disappointed and he will be feeling ashamed of himself.
In his shoes what I needed when it was me, was someone to listen to what was going on with my peer group, understand how unhappy I was and to help me find a way through.