Kicked back about a foot" is pretty wild but honestly that's just a dull blade or feeding it crooked. People act like every kickback is a near death experience when half the time the board just jumps a little. Get a roller stand and stop overthinking it lol.

Had the same thing happen with my old Frigidaire, thermostat was reading about 50 degrees high so everything came out underdone on the bottom. A cheap dial thermometer hanging on the middle rack told me the truth right away. What I learned is that drift usually comes first, the thermostat just wears out over time, and the element going bad is a whole different deal, you'd notice that as uneven heat or a coil that stops glowing. So yeah, check the thermometer every bake day like you're doing, and if the gap keeps growing you can sometimes adjust the calibration screw behind the knob. Also worth checking the door gasket while you're at it, a bad seal can fake a thermostat problem.