tense - Why is it not OK to use the Present Perfect here?

Michael Swan, in his grammar book, says that in this context the Present Perfect tense is not to be used.

1) Why are you crying? – Tony hit me.

2) This picture looks great. Did you paint it yourself?

I don't understand why the following are wrong, in his opinion. Could you shed some light on the factor I am missing?

These are apparently wrong. Why?

3) Why are you crying? – Tony has hit me.

4) This picture looks great. Have you painted it yourself?