It could just be that when you push the brakes the fluid level goes below the proper level. add fluid and see if stops.
May have air in the system and have to be bled Check the flexible brake lines (front) to make sure they are not ruptured and are ballooning when brakes are applied
Check parking brake if you use it. Sounds like broken cable.
Vacuum brake booster is defective or the hose going to the booster is leaking.
no
929 1990 Mazda power brakes fails
Check the pistons inside the calipers, usually they are the reason brakes lock up.
To add brake fluid in a 1990 Mazda Protege, you need to locate the brake fluid reservoir and check the levels. The reservoir is located on the master cylinder for the brakes.
Parking brake (also known as emergency brake) foot pedal expands the rear brake shoes against the brake drum holding or stopping the vehicle in an emergency situation not as effective as regular service brakes
Check your brake fluid level in your brake master cylinder in the engine compartment and see if it is down.
Check the switch at the brake pedal .
I'm not a mechanic but I would start by checking the brake fluid level in the brake master cylinder in your engine compartment
did the parking brake get set, or the shoes adjusted too tight?