Dodge Charger Question?

Well, if you have an electric motor that actually turns the wheels versus an older hydraulic power steering pump then it likely runs off of the battery so even if the engine wasn't running and the key is "on" you can still steer. Maybe your battery is too low, too often. Far too many people don't spend the extra money to get a higher AMP alternator when they install any aftermarket stereo stuff so the battery gets sucked dry while the stereo is on while driving. If the power brakes are hydraulic boost powered or vacuum powered then you need to check for any vacuum leaks or fluid leaks around the master cylinder and brake lines. If the power brakes are also electric in nature, then a low battery would also rob power from the brakes since they should also work in the event the engine stalls while driving. 

Get an alignment and get the steering rack and ball joints checked.  Flush the brake fluid and bleed the brakes.

The ABS system doesn't effect the brakes by making the brakes "feel heavy" When the ABS system activates the brake pedal will pulsate but the brakes will work with power braking. I'd go to the dealer.