Running slow after replacing power button and sensor ribbon cable

i just recently replaced the power button and ribbon sensor cable in my girlfriends iphone 4 and now she mad at me because the power button stopped working the head phone jack doesnt recognize headphones the light dark sensor doesnt work the phone doesnt vibrate and now its running extremely slowly. i believe the part i replaced it with was defective which explains the sensor and power button issue, and im sure the headphone jack and vibrator are just put back incorrectly and would be really easy to fix but i have no idea why its running so much slower now, really could use some help and suggestions