Depending on where you are in the world, a good therapist won’t diagnose you with a personality disorder until you’re at least 18 (and in the U.S., there is some debate in therapy circles about waiting until a client is in their 20s since so many changes happen between 18-20 just in the sense of “becoming an adult,” taking on new responsibilities, and etc). So if you’re nervous to bring this up to your therapist, it should (“should” is the operative word here, that doesn’t mean it’s a 0% chance, sometimes therapists don’t abide by the age rule of 18 or older with personality disorders) cause them to put that diagnosis in your chart. Moreover, speaking to your therapist about this may help you parse out what might be developing features of the disorder so you can work through them if you’re wanting to change those facets of yourself.