Welcome to the BP club!!! The depression is pretty much covered by the BP diagnosis and while you can have a dual diagnosis of BP and BPD you may find that the BPD was a misdiagnosis for the BP, I say this because you said that you didn't really fit the BPD and they can be tricky to tell apart. I wish you luck in you journey and hope the doctors can get your meds sorted quickly and you can find some stability really soon.
Take it easy on yourself, it's hard to come to terms with the diagnosis even if you were expecting it