2000 Acura Integra check engine light

I own a 2000' acura integra ls with a 1.8 non vtec engine. I recently had my timing belt replaced due to it breaking off while I was driving approximately 40-50 mph on the street. I took it to a shop to get it fixed and when I got it back, the check engine light would blink when I start the car. When I start driving, the light would stop blinking and would just stay lit. I also noticed that the cars performance isn't quite the way it was before. Loss of low end torque and acceleration, and loss of top end power. Does anyone know what can possibly be wrong with it? And if so, how much am I looking at come time to have it repaired?