2004 Pontiac Grand Prix Hit another car

2004 Pontiac Grand Prix 6 cyl Automatic 64000 miles

I hit another car going approx 20 mph while I approached a speed hump (he was just leaving the peak of the hump). There was no visual damage whatsoever to either car but I am worried that maybe his frame was shifted. He drives a small sedan, I think it was a nissan but I'm not sure what type. Approximately how likely is it that I shifted the frame of his car? How much would that cost to repair?

Thanks.