I am a stranger on the Internet, so please take my input with a grain of salt.
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A lot can change from the age of six. You may test differently now, if you were to be reevaluated.
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Good academic performance, especially in standardized test, might demonstrate that you are intelligent, but they do not preclude other deficiencies.
For example, your post is disorganized, riddled with errors, and difficult to parse. You said, "am lazy to edit." This might indicate that you have difficulty communicating clearly, perhaps emerging from hyperactivity or focus issues. Autism often comes with communication issues.
Other people can't see your standardized test scores on your face, but they can judge you immediately by how you communicate. That might explain why people call you "stupid."
I might be completely off the mark. If you do find that communication is a difficult point for you, then the good news is you can practice anytime. Just talking with others, getting older, and building experience will bring you up to speed with diligence.
Finally, there is a negative social stigma to intellectual disability. Try not to buy into it too much. I used to teach 12 year olds how to read. Some people never learn how. They were all intelligent, they just need to step back a few grade levels and have a helping hand. Sometimes you do need to reach out for help.