I think Weed gave me mental health problems

I think that weed may have given me mental health problems. Firstly i understand its impossible to prove cause and effect however some of this stuff may be interesting/ useful to some people reading.
I developed depression soon after smoking weed with my friends one night. Although I never smoked it again, ever since that point I developed severe mental health problems and I have developed some other disorders along the way.
About two years ago I smoked only a few hits of weed and I felt extremely strange and particular anxious. I didn’t think anything of it but soon after I was diagnosed with severe depression and generalised anxiety disorder. It’s impossible to prove cause and effect but I had never suffered with depression befor this point and I used to be so happy and excited. I completely changed over a few weeks.
Fast forward two years and I have every symptom of severe depression as well as a dissoaciative identity disorder( which I’ve had for a few months), as well as psychosomatic pain disorder(which I’ve also had a few months). Also a few weeks after smoking weed I developed a condition that affected my joints but that eventually went.
However, after smoking the weed I did notice that some pain in my body stopped. For example for about 3 months before smoking it I had eye pain that could not be explained by doctors. I went for loads of tests and had my eyes checked at a hospital and they couldn’t detect any problems. A couple of days after smoking weed my eye pain was resolved.
I ultimately will never know whether these things wouldn’t have occurred whether or not I had smoken. However, I do strongly believe that the mental health stuff was linked but maybe not the other stuff.

This is because before smoking that night I was a completely different person, I was excited,energetic, hopeful and extremely motivated with high achieving goals. A few days after smoking I started to become severely depressed and started questioning the world and it’s just gone extremely downhill since that point. The new disorder I have is where my mental state causes severe physical pain throughout my body.
This is probably a rare thing to happen if you smoke weed, however I would of loved if I read a post like this before I smoked. I had plans to study at oxford and start up my own business, and I was predicted all A’s and A*s in my a levels( I also achieved all A*s and A’s at GCSEs). Now I am in so much physical and mental pain that I am unable to keep a job and have to rely on my parents to do everything for me.
I have read similiar cases of things like this happening but it’s so heartbreaking. No matter whether smoking caused this, didn’t cause this or only partly contributed it has changed my life forever.