Not as long as the light is bouncing off the wall.. but you can be injured if you catch a reflection off of a glass/polished surface (these are called specular reflections) or if you catch a direct beam at that close range. Generally speaking you should avoid direct or specular exposure to scanned beams at all times unless absolutely necessary, or unless you've made very accurate measurements of the distance from the aperture to the nearest set of eyes that will be exposed, along with beam diameter/divergence measurements and power measurements made using a calibrated laser power meter with a 7mm aperture over the sensor. Doing the math is the only way to be 100% sure your show is safe, and you must take measurements while running each type of scanned effect that will contact the audience.
There are some cases, like your specific scenario, where one can be very sure that the exposure will be safe without taking the full battery of measurements AS LONG AS the show is private not public.. ie on your own property to a private audience. Since the power level is fairly low, and the nearest exposed set of eyes will be 100 feet or more away, the possibility of retinal damage is very remote. You MUST still be sure that your distance and laser power measurements are accurate, not guessed.
