Intelligence Quotients: science or pop pyschology?

My IQ was tested every couple of years from Kindergarten age through junior high or so.At some point after that, my mother told me that my scores went down every time I took the test, although I never learned what the scores were.I found out much later that this wasn't important but it was rather troubling to me at the time. Was I becoming dumber?I have looked through some IQ tests over the years and I feel the same about them as I do the SAT's.Some parts are incredibly easy for me, and some parts might as well be in a foreign language.