If you can get a good image of femoral pores and if you gently lift his/her tail with him/her facing away from you you should be able to see two bumps at the base of the tail if it's a 'he' or one bump or no bumps for female.
Here is an image of my male water dragon taken when he was about 8/9 months old

(Ignore the date on the image, the year is out by 1. It was 2006 when that image was taken.)
I would also have to agree that yours does look female. The black stripe behind the eye doesn't appear to be as strong and definate as a male's would.