is this your first ivf? either way, it is normal to feel nervous after transfer. because you know that you have an embryo in your uterus... you want to protect it and nurture it... this is how i felt at least.
try to relax (take deep breaths) and enjoy the 2ww ride. you've survived the ivf treatment and now let the embryo do itself... implant and grow.
good luck and wishing you a BFP.
Sounds like nerves to me. It certainly wouldn't be the baby moving. :)
Good luck!