Secret Shoppers

I have this friend whose therapist says she's mildy paranoid. Okay, honestly, I am talking about myself, and I obviously work in customer service. Luckily, it is not the kind of paranoia that's severe or where I think someone is trying to kill me. Usually I think someone is tricking me, setting me up, lying to me, or just testing me. In my personal life, this has often been the case! Ever since I started in retail, I've had bouts of thinking customers were secret shoppers. I mean in a stream of 15 customers I will feel like they don't feel real at all, and they can't be "real" or authentic. Every single person in a long stream of customers will feel like a secret shopper! I mean, nobody could really be that rude as to yell obscenities in public, or nobody could be that careless as to leave behind 17 movies, and then expect the store to replace them one month later, right? Or would a woman have a fit over three cents to which she felt entitled? I've seen that happen more than once. Both times it was three cents, not two cents, or a penny. Or when I had to return and resell an entire order totaling close to $300, that seemed like a setup, especially since I knew the person. My friend's therapist, oh, I mean my therapist, says that possibly what is happening is that my extreme sensitivity is picking up on something, but then I misinterpret the something. For example, I'm recognizing there is something "off" with each person, but I am thinking "secret shopper" when it is just someone who is having money troubles, is embarrassed, or is angry at himself and taking it out on me. Another thing my therapist taught me is that when anyone is angry, whether we are talking about a customer, a significant other, or myself, there is always at least a little part of that person angry at himself or herself. I really believe this to be true. Another thing is that there is always a part of myself that knows my employers, past and present, are not going to be spending the kind of money it would take to hire dozens of secret shoppers, especially not every day. It is not like I don't recognize my thinking is a little paranoid. So, part of me is thinking, secret shopper, and another part is saying I'm just overthinking everything and being my sensitive self. I also think that though I wouldn't return very worn, oil stained, torn, and duct taped shirts and pants, that there are other people out there with their own emotional issues which would bring them to feelings of entitlement to replacement clothing, and thus, this would bring them to me!