Answer: yes it could have bent some valves or damaged a piston with one or more of the valves( could have punched hole in piston or smashed piston so hard that it damaged a bearing)
This would be a warranty item. Talk with your dealer. If the tires are worn out, they will make you think it is a bearing(s, and you will have went through the expense for nothing.
I would suggest you replace the fuel filter. See where you stand after doing that.
The Neutral Safety Switch on the 1997 Mazda 626 (and similar) is located behind the clutch petal arm. The petal is connected to the clutch master cylinder pushrod which goes through the firewall. Right below it is a little black box with a short white plastic rod sticking out of it touching the petal arm and a wire harness attached to the box. The box is the switch. The white rod is the spring loaded part of the switch that is thrown when you push on the petal. Two small bolts hold it in place. It is quite hard to get to and see. You will need to push the driver seat back all the way. A small flashlight or other lighting device is needed. You will be on your back, upsidedown, and in a fairly uncomfortable position. It is a non-serviceable item and should be replaced if it is defective. However, if one is careful it can be taken apart and cleaned. THE FOLLOWING SHOULD BE ONLY A TEMPORARY FIX AS IT BYPASSES THE SAFEFY MEASURE DESIGNED INTO THE CAR: If the rod is broken, it can be short ciruited to start the car by removing the spring and pushing in the remaining part of the rod.
read the owners manual that came with the car