Ice,
Since nobody else has said it yet, that location for the pressure sensor is not optimal by any means. You'd be much better off t'ing it into your return line (outflow side) from the filter to the motor as that will give you a much better idea of what oil pressure your crankcase is seeing and a much quicker response to dropping oil pressure as that will be the first damaged area.
Other than that, you most likely didn't cause any serious harm if there was oil allready in the motor which it sounds like there was.
Rick
