IUI and Testing

Hi everyone! I had my first <a href="https://glowing.com/glow-fertility-program">IUI</a> on December 15 and I am supposed to be testing tomorrow after this horribly long 2ww. I am soooooo nervous! I haven't had any symptoms besides feeling bloated and a little cramping (similar to AF) today. Just wondering if anyone else had similar symptoms, or any symptoms for that matter, and got a BFP. I really just want to know other experiences. Please ease my mind! 
Ps. Glow says my period isn't supposed to start until January 3rd so would it be too early to test even though my 2ww ends tomorrow?