I was driving down the highway nicely (no.

I was driving down the highway nicely (no problems before this) and a bump sounded under the car. I did not hit anything, but the next day it started shaking, having trouble going uphill without being put in D2 or Low (something I have never done before), and seems to want to cut off when I am stopped although it has not done it yet.

I had just had an oil change and a tire rotation done before this.