I've been told that in the US (somewhere in these comments) that IQ was tested according to reading comprehension at schools. That is not how IQ is tested. You would have had to do an IQ test that involved many different logical skill sets.

It is true that people with high IQs tend to not put as much effort into things - that's because they pass school tests with little effort and they can do many things with little effort.

I have never cheated in my life. If you had to cheat, you probably weren't gifted. The best way of finding out whether you are gifted is to do a test at Mensa or a doctor. Then you will know for sure.