Damn quantum mechanics

A diagram such as this one:



Is not so bad to interpret. A particle flis along, emits a photon and so changes course, then gets hit by another photon so changes course again.

But by a simple reordering of events, which is perfectly allowable in quantum mechanics, and in fact extremely necessary we get:



Now it looks like a particle flies along, emits a photon and starts going back in time for a while (or bounces off a photon from the future?) gets hit by another photon and starts going forward in time again. Weird.
Fortunately there is this whole interpretation of the going backwards in time part as being an antiparticle going forward in time, so that first a photon decays into a particle-antiparticle pair, then the antiparticle annihilates with the initial particle releasing a photon while the other particle goes free. This is sort of nice, but on the other hand it almost seems like the going back in time thing is a more cohesive idea, since we must take into account all possible such processes when trying to figure out the result of such interactions.