Sure, just look at the opening verse: I doubt the veracity of that statement, which leads me to doubt that the statement was every actually uttered. Much of the book appears to be written using hyperbole to an extreme degree. As to the authenticity of the book, I doubt that it was actually the disciple who recorded these sayings, but just someone who attached his name to it. As to actuallity of these being sayings of Jesus, well I suspect that there is some truth to at least some of them, but the aforementioned hyperbole and differences between some of the statements found in Thomas and what seem to be parallels to passages within the canonical gospels lead me to suspect that those sayings have been changed by one or more author(s) since they were first spoken. There are also some difficult passages in it such as So, I find it interesting that some who reject the canonical gospels might be so enamored with the Gospel of Thomas.
So, I don't think that Thomas is Q. But as it presents itself as just a grab-bag collection of sayings, and (on the whole) doesn't contain anything so antithetical to the view of Jesus presented in the canonical scriptures, I do think it gives some credence to the idea that there did exist a collection of sayings of Jesus (I suspect in oral form) that we known and used by the early church prior to the production of a written record. And I suspect that the early church ultimately did not recognize Thomas as being worthy of classification as canonical primarily because it wasn't really believed to have been the product of the disciple Thomas (despite the claim to that case in the text) and because the hyperbole of the text lead it to be viewed as less profitable as a guide to faith and practice than the other books that were accepted were found to be.
That's more than you asked, but I thought I would go ahead and anticipate future questions and just lay most of my views with regard to Thomas in one post.