Can driving 60 or 65 mph in Low Gear cause damage

This was a brand new car, and I mistakenly put it in Low Gear. By the time I realized, I had driven around 4 miles, but had gone as fast as 60 or 65 mph.

Since accidentally driving in Low Gear, it has felt like the car hasn't accelerated as fast as it should, and that it lingers in higher RPM's as I accelerate, only going back down to the 1xxx after I release the gas pedal. Again, I don't have any true point of comparison, mostly going based on feel compared to previous cars I've driven.

Are there any damages I should expect, and/or warning signs? Is this cause to take it to a mechanic? Any help would be greatly appreciated!