Check you brake fluid level. It might be low.
Also, with the car pulling to one way or another when you apply the brakes can mean anything from a caliper, pad or rotor problem. If you are not mechanically inclined, you can take it to a dealer or brake service place for an inspection and estimate.
Also, please add your year and trim of your vehicle to your signature line. That way when you start asking questions in other areas of the forum, we all have a better idea on how to assist you. Click on "Quick Links" above, go down to "User Control Panel" and then click on "Edit your Signature" It'* pretty straight forward from there.