Is there anyone else here who thinks all IQ tests are completely bogus?

I've taken several, both real and fake ones and my scores literally range from retarded to genius (far too great a margin of error for any score to even be accepted as valid in any sense) and I've noticed there is a direct variation pattern with my mood at the time of the test rather than anything else which leads me to believe that the tests are completely bogus. Besides, intelligence as such is something I've always viewed as a hypothetical construct and do not see how it can be properly and accurately measure in numerical terms. I know many of my friends seem to score consistently on such tests but I never do and I don't suppose such an 'accurate' measure of anything would allow for so much margin of error or allow for exceptions where certain scores are inconsistent or else it would be wrong to call it accurate. This has led me to believe IQ tests measure nothing but the amount of alertness and interest exhibited by the take of the test at a certain point in time as opposed to the more conventional view that it is a measure of intelligence. Is there anyone else here who agrees?