Long drive tomorrow, wheel just started screeching, need advice

[Qwoz]

So i'm making the long 5 hour drive from Pullman to Seattle tomorrow and my rear right wheel just started acting up. My number one guess is there is a rock stuck between the rotor and something like a heat shield (example shown in video 1). I have had a rock get stuck in the breaks briefly before, and it sounds a lot like this... but this is more persistent. The sound changes from what I could analogize as a rock shaking around in a coffee can, to a loud screeching. Video 2 shows another example of what it sounds like, and the video poster claims it to have been a rock. Video 3 is one I took this evening. probably 10 seconds into the video I start swerving back and forth, and you can hear the sound get quieter and then louder. This is one reason I entertain the idea of it being a bad wheel bearing (I sure hope not :frown. It is also helpful to note that there is no vibration at all, as you might expect with a bad wheel bearing. What do you think? Should I drive it until it the rock hopefully flies out, like most rocks will? Or does it sound more serious. There is a lot of construction going on around my house, so it would not surprise me at all if it is just a stubborn rock. Car has 45k miles on it.

Video 1: https://www.youtube.com/watch?v=cGSX8VyhJI8
Video 2: "SEXY" lol https://www.youtube.com/watch?v=sVaC-sjifdk
Video 3: My car https://www.youtube.com/watch?v=lyenz6I-QjI&feature=youtu.be

 

[Qwoz]

It was a rock and fell out on the freeway, just in case anyone is dying to know lol.