What do you mean too bad? If its a 100 mW laser it could blind you instantly, well instantly fry that part of the retina the beam hits. Reflections are definitely NOT ok, diffuse reflections on a dark matte surface wont be too bad, but it'll depend on your distance from the reflecting surface. IF however you have a specular reflection it will be very bad.
Don't risk it! Wait for the glasses if you want to use it indoors and don't even consider burning with out them!
As your eyes are less sensitive to 405 nm (Vis - near UV), than they are to more "visible" wavelengths, the beam will not appear as bright and as a consequence the the dot too will not seem unbearably bright. This does not mean that it is any less dangerous.....
This is not good advice! Please don't make dangerous suggestions, even if you understand the risks others may not!:tsk:
Edit: Lowell Beat me to it!