What Causes Sharp Pain In The Left Thigh?

My wife has been exercising over the last few months. While doing squats with dumbells she complained of a sharp pain on the side of her left thigh. Two days later, while doing the same exercise, she felt wha she described as a tearing feeling, like cloth tearing. It started from the point where the sharp pain started and moved up her thigh about 5 inches. Now when doing squats today, she notes there is a bruise the size of a quarter, and after exercise, the thigh area is numb and tinging. Ideas?