Hi,
The two problems with use of English posted some time ago are still not fixed. Hence, I'm still struggling to get to grips with this lesson.
"If I went to the hairdresser's" in English means; "If I were to go". They are equivqlent.
Similarly. "If he had an accident" is equivalent to " if he were to have an accident".
In both cases, the first sentence is common usage. The second using the the subjunctive is very uncommon in everyday English.