New serpentine belt squeals?

My dad replaced the serpentine belt on my car (07 Ford Fusion SEL) last weekend when I was home. I noticed my car makes grinding noises when I reverse it and a squealing/peeping noise when I turn now. Should I take it in and have a mechanic look at it? My car has never made that noise before, so it has to be from the new belt.

If you don't know how to diagnose and fix it, then yes, take it in. If you want to do it yourself, read these two posts:

http://ricksfreeautorepairadvice.com/diagnose-a-belt-tensioner/
http://ricksfreeautorepairadvice.com/diagnose-belt-noise/

See if that's really what's squealing. Spray a bit of water on the contact side of the belt and see if the sound stops or changes, and be very careful to not wet up the alternator. A squealing belt might be from it being the wrong size, not installed tight enough, or having one of its pulleys dragging. Take it to a mechanic if you can't test this. I would remove the belt and turn each pulley by hand to see if any are binding up.

Check your pulleys that are around the belt they might have left over grease or oil from previous work on the car if so clean them with water and a clean towel. Maybe try brake cleaner then rinse it off well with water and scrub the new belt with water and a soft bristle brush. But maybe one of your pulleys is damaged I've only heard of the belts/pulleys being oily and squealing.

2 possibilities for the squealing. Serpentine belt tensioner needs replacing or serpentine belt just installed is cheap Made in China junk that's killing the automotive world due to poor quality control.