Do I need visa, 4- day sightseeing side trip 4th week of Nov.

I live in NY, dual citizenship US & Phil. I am visiting Phil in Nov, & plan to see Beijing as a side-trip, via Guangzhou where my airplane stops over. I wasn't aware about the 3-day no need for entry permit, do I still need one? Or should I just cut a day out? May I use just my Phil passport($30), instead of US, that's has higher fee, if ever I really need an entry permit?