It’s normal for your pup to look a little forlorn when you’re about to leave the house (that’s what puppy-dog eyes were made for). Fortunately, most dogs learn to cope when their owners are gone. But for others, being without their human can leave them seriously stressed out. In fact, up to 40 percent of dogs with behavior problems are diagnosed with separation anxiety, according to research in the Journal of Veterinary Behavior. While it can be tricky to distinguish between normal or bored dog behavior and separation issues, we talked to a few pro trainers who helped highlight the differences. Worried your dog might be a little too attached? Take our quiz to find out.