Would parallel universes work this way?

I’m writing a sci-fi story concerning parallel universes and I’m trying to incorporate a plot that’s rather complex.

Now we of course don’t know for a fact that parallel universes exist, so I can just make up whatever rules I want so long as they are consistent, but regardless – I still want to see if this could be logical in reality.

Let’s say we have a guy just named John. John experiences a dramatic event in his life and responds to it in one of three ways – indifferently, positively, negatively.

So ultimately, there are 3 parallel universes – one in which John reacts indifferently, positively and negatively.

Let’s say one of those Johns decides to travel back in time to that dramatic event and respond to that event differently.

Does this eliminate the other two parallel universes that were created?