The most important is don’t panic. You are gonna receive an accurate diagnosis. You weren’t very lucky with this first psychiatrist. I say it mainly because in order to receive the right diagnosis the professional have to take time to assess you so I understand that you are now a little lost, not knowing what’s the core of your issues (Even professionals have sometimes problems to hit a diagnosis).

Look if you want we can share via pm experiences.
I also lived a period of my life when I was very confuse about what was happening to me.
The fact that many psychiatrists are so reluctant to give a diagnosis doesn’t make things better.

It happened to me something similar to you. First I was diagnosed with Avpd traits. Then, I went for a second opinion, I took note and described how I could have borderline PD. The doctor said that I hadn’t but at the same time, his report for my therapist said: Emotional disorder, beside depression and anxiety. But these two latter are in this case, symptoms.

Whatever you have, I’m sure you are gonna take advantages from your personal search along with your therapist’s support.

I wrote a lot in the borderline personality disorder forum quite a long time ago. It was mainly about information of the disorder. Even when you may not have the disorder is very interesting to know about it and learn to manage your emotional instability.
As AceRimmer told you, DBT is very helpful, not only for people with bpd but also for people to learn to manage emotions. As it is a long program and it is not available in many places. Don’t worry. The work you are doing with your therapist can be very helpful and (s)he may apply very similar techniques to the ones worked in DBT. In the end, DBT is more a technique than a whole therapy.

Again I offer you pm contact in case you need a little of my insight. Of course, I’m not a therapist. I only have my experience and what I learnt from bpd.