I'd give it a few days before really starting to worry, because the postal service (even with "express" shipping) can take ages. I've had packages delivered that arrived like four days after they'd reached the main post office in my city.
Funny story - I had a Tama get sent to Ontario, California instead of my city in Ontario, Canada because someone obviously just didn't think that reading past "Ca" was necessary! It made its way over to me in one piece after a quick phone call to tell them "uhh, wrong Ontario guys."
It is usually much more worrisome if your package gets stuck at customs, rather than in transport within your country. 99% of the time, if something coming from overseas gets "lost in the mail" it's because it got held up at customs.
Sending vibes over your way for your Tama to get here quickly!!