How do I know if I really experienced what I think I went through?

You can do reality testing by checking with other people who witnessed the event. Check with them. But listen to what your gut is telling you too.

Well everything is based on perception and memory is imperfect. So if you wanna know if you went through something, take a picture of video tape it, however it may not do any good for past events. You can never know anything for sure, it's due to how our brain is.

You can ask someone who may know about the situation to get a better understanding of the situation. Also, for traumatic experiences, therapy can also help uncover hidden memories. Your brain has a natural in-built defense mechanism called repression, where the brain stores stressful memories into your unconscious. It can be recalled through serious thinking, second opinion and sometimes through therapy!

If you feel it happened, there is a strong chance that it happened. I know that, for years, I thought I was making up my trauma, trying to be an interesting or weird kid. The question I always asked myself in response was, "How would you have known that experience specifically if you hadn't experienced it?" Eventually, in therapy, I found that that type of coping, the not knowing if it actually happened, was a dissociative survival skill to help you understand what you couldn't at the time.

You could line up facts. Go with what you know for sure is correct then find if other spots don't add up.

If you feel it happened, there is a strong chance that it already happened because how can you think of something that did not happen.

Don't ever doubt yourself. You and you only went through your experiences, no one else. Self doubt can be really crippling.

You are the expert on you and your emotions are something only you can feel. Nobody else can tell you what you can or can't feel, emotions are out of our control, we can't just switch them off and what you feel is real and valid. nobody can tell you otherwise