Past Perfect Tense

[RG781]

I have a question regarding one of the drills in the Foundation of Verbal book.
It was written in the book (p. 55 and 56) that you are not required to use the past perfect tense when you have 2 events that took place at different times in the past.
However, in Drill 3.4 - 4 "The doctor told me I had a heart attack" was incorrect, and it was explained the the sentence should have "had had" as a past perfect tense.
I am confused, isn't it right not to use the past perfect tense?

Thanks

[RonPurewal]

"had ___ed" is used for an earlier action/event whose completion is important in the timeframe of the sentence (which is later in the past), and/or that has a clear impact in that timeframe.

in this example, both of these things are clearly true: the heart attack is over (since the person is talking to a physician about it), and it obviously has a huge impact on the situation at hand (since it is the entire reason why the person is talking to the physician in the first place).

__

by contrast, if a sentence just describes two essentially random past events in sequence (e.g., we ate dinner and then went to the club), it's incorrect to express the first event as "had ___ed".