You need to put a good scanner on it when the lights are lit to see what the codes say. The scanner should also tell you which wheel is affected if it is a sensor. I haven't done one on a mazda, but did on a kia. It was possible to just change the sensor but it was easier to change the entire wheel hub.
Can you do it? Depends on your comfort and ability to work on vehicles. Search for videos on wheel sensors or hubs.
But first, you need to see if that is the problem. And yes, it could have been low brake fluid as that has been know to trigger those 2 warning lights.