Gender Re-Scan Advice ?

Danielle • Mommy to a precious little boy born 12/17/15 and full time working mom! I love my little family!
Hello all!! Quick question... I had my gender scan yesterday at 15+3. Tech couldn't tell if baby is a boy or girl because the cord was between its legs (once I did acrobatic stunt work to FINALLY get baby to flip over). She said 90% sure of a boy. I have another appt. Tuesday to confirm. Anything I can eat/drink different to get baby to move around? I had sprite and jelly with breakfast and apple juice an hour before my appt. That didn't seem to work. 
I've also been having a pregnancy induced heart arrhythmia and am supposed to avoid caffeine to help keep my heart rate down. 😞