The whole no manic episode until your 30 thing is false. I didn't have my first 'true' manic episode until I was 34. Before that I had some hypomanic episodes but was always more on the anxiety/depressive/OCD side.
From what you wrote it sounds a lot more like BP2 than BPD. If you are able to have healthy interpersonal relationships and don't manipulate people I don't see where your doc is getting that diagnosis.