Why does my counter count strange values?
Most probably your sensors don't generate sharp enough edges to be used as a clock. That would explain why your circuit works with toggle switches.

You should pass the signals from the sensors through Schmitt triggers, if you want to keep your current design. If you were to start from scratch, I would advise NOT to use input signals as CLK altogether. Get a nice and clean clock signal from the resonator, and make your system sample sensor data often enough so that no human could sneak through in between the samples.