Q: Electrical components not working in my car

The symptoms described for your Mazda indicate that you may indeed be dealing with a dead battery. As batteries age, they lose the ability to hold a charge and typically need to be replaced. Combining age with accidentally leaving a light on after you exit the vehicle and this can put that final nail in the coffin for your battery. However the battery needs to be inspected to determine if a recharge is also an option. If the battery is not old and the water levels in the battery are good, a recharge can be performed. This will allow the battery to be tested and can determine if the battery will still hold a charge or if the battery needs to be replaced. I highly recommend enlisting the assistance of a certified mechanic who can verify and perform these repairs for your Mazda.