Good Point OP;
I look different in Mirrors as well, depending on the light / Angle - and It can make me look terrible if its at night time in an outside reflection under light e.g. Car Windows
I look different in mostly every photo aswell.
I would love to be able to see my true image of what people see when they look at me - I hope its not the terrible version, but considering that it's only when its under a certain mirror angle or light :/.
I always assumed Camera's didn't pick up all my skin detail so made me look better than I actually do , same with Mirrors?