Hi David. I loaded your image into Aladin (a very useful free program that you can download for free from here) and marked the position of the comet at the time of your observation (the pink cross). The faint fuzz is certainly in the right sort of position but it is difficult to be certain since it is so close to the detection limit and it could be an artefact. For very faint objects like this it is worth getting two stacks separated by 30 mins or so. When the two images are blinked any faint comets become obvious from their motion.
Anyway, this is certainly a very good attempt. Please keep trying to image this object.