Francy, Just For The Heck Of It, Put In Some Gas Line Anti-Freeze.
This stuff goes by other names. DRY GAS is a Cristy brand. It could also be called gas line-drier.
My theory is that maybe you have a little water in your gas tank. It happens to the best of us. Being more dense than gas, it settles in the bottom. Gasoline rushing in during a fill-up stirs up the water. Your car struggles with water in the gas until it settles out.
If it's cold where you live and it was toasty warm inside "Quicky Petroleum", and particulary if your tank was low and already had a little moisture, then going from cold to warm to cold, could have added condensation (water) to your tank.
(This is for Hello Kit, Good theory, eh? Did I miss anything?)
Whatever the outcome from all this excellent advice everybody gave, let us know what happens.
Follow the Dry Gas instructions and maybe get two. Use it for two tankfuls. Also, try letting the car sit several minutes after the first 2 fill-ups.