If you lay in the bed, depending on if you are lying on your back or stomach, left and right still change.
Ususally a bed is positioned with the head against a wall, so if you are facing the bed from the foot end, left and right are always the same. So I vote left/right is as seen from the foot end of the bed.
My washing machine has this repeating beep too. If you haven’t done so, check the manual: on mine there’s a setting to disable it.