Gender guessing!

I'm so eager to find out the gender of our little one. At my 12 week scan LO was jumping around and moving constantly. I've had no tender breasts, no morning sickness, the only pregnant symptoms I have had are headaches when I wake up and trouble actually finishing my food! (Sounds crazy right). My 20week/Gender scan is next month. But I'm wondering is there any 'old wife's tales' that suit the description of how my LO is that could give away his/her gender?