TTC#3- The link you found is the same as the nub theory...it's definatly not a guarentee as there are PLENTY of nub guesses on the u/s forum that we have professional u/s techs look at and they have been wrong. However...looking at your nub it's very flat...although the picture isn't clear on the computer it appears to be less than 20 degrees to the spine which is typical for a girly nub....all fetuses before a certain stage look the same "down there" the elongated part we see will turn penis for a boy and gradually sink in for a girl, it's the clitoris, and the outer fold will turn labia for girl and scrotum for boy. SOMETIMES boys can look very flat and still be boy and vise versa...but I think a lot of the time it's right as well. I hope that your nub is correct as it looks girly to me! The boy nubs tend to point up or are forked. Go to the u/s gender prediction forum and take a look at a few! Good luck!