A Stupid Decision Ruined My Progress!

Hello all. I have been a user of this site for just shy of three years now since my breakdown in 2017 upon starting University for the first time. I have been on a long journey of self-reflection and feel like I am relearning life itself sometimes with all this adulthood stuff I repressed in my head for so long. I have been on Citalopram, Mirtazapine, Sertraline and Fluoxetine with varying degrees of success, however right now I am medication free apart from the occasional prescription of Diazepam for my panic attacks. I have had ups and downs with my anxiety ranging from having months with little amounts of anxiety that I can push to one side to times like now where my outlook on life is so immensely bleak that I think I will never get out of the rut I am in since the concept of this feeling never leaving can be so real. Two days ago I made the awful, reckless, naive, childish and just plain bad decision to try a recreational drug (I want to stress I am NOT NOT NOT endorsing any person here to ever try these no matter what your brain tells you, it is NOT NOT NOT worth any risk) and I feel I have made the worst decision and ruined my brain. I took 50mg of a drug known as 2C-B as my friends have said about how it makes them feel good about themselves and helps with anxiety.(again do not use what I am saying for a reason to take anything like this, it is NOT worth it!) I end up having an awful, delirious experience in which I thought I was really dead for half an hour which is terrifying when you suffer with Health Anxiety. I had gruesome visions of seeing myself in a car accident and it was a really unpleasant experience. I am in no way addicted to anything and I very very rarely do anything like this and it was out-of-character for me to do so. I came out of this with an awful non-specific anxiety which I have had before during a trip to York I took in which I was tearful and got over-emotional at everything; good and bad it would make me cry tears of joy or sadness. I have dealt with exceptional intrusive thoughts that have left me stunned (such as stabbing family with knives) and they can bring me to absolute tears since I cant even kill a spider without getting upset at the thought of me ending the life of another animal. These thoughts have been exasperated by this experience and I keep having thoughts of my aunt passing as she is literally the kindest and most compassionate person in my life and she has literally done everything for me, and I currently live with her. She is literally my rock and just imagining life where I cant talk to my literal best friend is bringing me to tears just typing it now. She is currently 70 and I think after her scare with cancer it made me realise that these people in my life arent going to be here forever and I just think its so cruel. I feel like doing what I did has just brought me back to where I was in 2017 and I really need someone to help me rationalise why after doing a drug it has brought the anxiety - which I thought I was getting in top of - back. I am terrified of losing my family, I am unable to hold a job due to the fact my mood can go from really good to really bad in the space of seconds with no cause, and my ESA renewal is coming up in December and after what they put me through last time I am even more terrified of it now. I feel like I have just ruined my life and I have messed my brain chemistry up from doing a stupid choice 2 days ago. Any help and advice would be appreciated! All the best, Kyle