if you fake the photo, you still risk the chance, of the police meeting you at the plane. Its not worth the hassle. I would just deal with it and not get into a pissing match with the lady behind you its really not worth it. The air vent may be annoying, and you do have the right to recline your seat. But is it worth getting detained and having to explain your story to the police when you land.
On a side not i would also write a letter to the airline about the FA. Reclineing your seat is a right pointing the vent at you is not. The lady behind you should have been asked not to do it and nicely explained why. You never threaten a customer unless it is a saftey issue which this is not.