There's a difference between the red BRAKE light and the yellow round light that indicates front brake pad wear.
One of the things that can trigger the red BRAKE light is low fluid in the reservoir. That's the first and least expensive thing to check first. If it is low and you add some fluid, keep an eye on it to make sure its not going down again. The reservoir level does go down slowly as all the brake pads wear - you just want to make sure the fluid level is not going down fast as in a leak situation.