Serious question about ptsd. looking for serious answers.?

I recently started therapy. I am a recovering drug addict. I have been clean for over 8 years and have worked the 12 steps hard. I have a very violent past. I ran with gangs and such. I have been going through a lot with dealing with my past. Like in every bodys life i have a lot of medical arm chair quarter backs diagnosing what is wrong with me. I was incorrectly diagnosed with depression. In a fifteen minute consultation with a physicians istant. the anti depressants made me aggressive and irritable. I am off them and still feel aggressive. I had a friend state he thinks i have ptsd. I have read symptoms online. I fit with the exception of recent trauma. Is this what I could be suffering from years latter. I am seeing a second doctor about some physical anxiety next week. Is there a good source of literature online, besides basic symptoms. Is their a support forum. thanks in advance.