In general, isn’t it better to put the Tracking code in the footer area (so that the content gets loaded before the tracking code)?
But, without looking at your code, make sure that you copy/pasted the code from Adwords and didn’t inadvertently miss some code.
If you comment out your tracking code (or otherwise disable it), will the page load correctly (without redirect errors)? If so, then the code is ‘damaged’ in some way.