weird Power Steering and ABS issue
 

I have been driving around and the steering is all stiff. When I first turn the car on it steers nice and smooth, then once I drive about .5 miles it gets real stiff like no power steering. The ABS light also comes on and stays on when the occurs.I just had my car in the shop and had the cv boot replaced, front rotors and pads and a new passanger side caliper. I looked under the hood at the power steering fluid level and I noticed that the darn cap wasn't even screwed on. The tank is full, so I put the cap back on and drove it around to see if it would clear up... but no luck... any ideas?