Welcome to the forums and thanks for joining us! I'm glad that you're seeing a psychologist and it sounds like they've been helpful so far although you're kind of stuck with the diagnosis; partly wanting to know and partly not?
I completely understand the stigma and misunderstandings associated with BPD. Somehow as a society we have more compassion for depression and anxiety then any other personality disorder. You only have to look at movies to see that characters with BPD are typically feared or incredibly dangerous, which is such a myth in real life.
With that said though, a diagnosis can also kind of be comforting. It explains things. There's a reason for what you're experiencing. You're not alone in how you're feeling and there's so many that have pretty similar experiences. What do you think is going to be more powerful or more helpful for you?
As for the schema test - here's what I can find out. There are certain things that psychologists/psychiatrists look for in the DSM-IV (the diagnostic manual) and the schema test can be a 'guiding tool' to help them see how clearly you might 'fit' in that box. Although there's a lot, some of the unhealthy ones they look for can be things like abandonment, shame, failure, abuse, dependence or approval-seeking. The higher-rated they are the more likely it can be that you may have BPD.
I hope that this helps a little!