Hi guys. I'm a 19 y/o girl diagnosed with Depression and Anxiety, but I feel like there is something we are missing in my diagnosis because none of the treatment we have tried has helped and I feel as if Depression doesn't encompass all my symptoms, especially ones that have popped up recently. If it matters, I currently take Cymbalta and Lithium. 

Anyways, on to what happened. I have been suicidal for some time, drifting between active and passive. Recently it has been very active, to the point where I had a plan of how I would do it, but didn't know when. Well today I was driving home and I decided it was as good a time as any to go through with it. I drove to the beach near my house and up to the boat ramp, where I intended to drive straight into the ocean as fast as I could. I got to the edge, just touching the water and something stopped me. Not some big moment of hope where I realized life was worth living or anything like that. I just stopped and my brain changed directions. I parked the car and got out and I walked into the ocean fully clothed, about thigh deep. I don't know why I did it. I stood there and stared at the water for a while, and then got out and layed down on the pavement, looking at the sky. Still not really having any thoughts. Then I stood up, took off my shirt, and walked to a different part of beach. I walked into the water again and just sat down. After a while I started to walk back to my car and I lost all my energy and just layed down in the fetal position in the sand. As I got up, there was a flare of activity in my mind and I ran to my car. When I got there I started screaming at the top of my lungs. "They can't find out I'm crazy" "They're going to lock me up" etc. stuff like that. I texted my boyfriend after that telling him I needed to run away and that I was leaving tonight. He called me and I said the same kind of stuff about being locked up and being crazy. He kept trying to calm me down and tell me I was having delusions but I felt so sure that what I was saying made sense. I still do to a degree. 

This whole thing felt like I was having intrusive thoughts but instead of ignoring them, I just gave into them. Idk I have never experienced anything like this before. Was I just having delusions/paranoia or a psychotic episode Could anyone think of a reason for this to have started out of the blue? 

If this isn't the right place to post this question, let me know and I'll happily move it somewhere else. I just am very confused and scared and I want to understand what just happened to me.