I was always taught that everything in the book of Revelation happens in strict chronological order.

I was taught, therefore, that everything in chapters 7 through 15 all happen after everything in chapter 6 is finished.

However, the following happens in chapter 6:

Revelation 6:13 And the stars of heaven fell unto the earth, even as a fig tree casteth her untimely figs, when she is shaken of a mighty wind.

 14 And the heaven departed as a scroll when it is rolled together; and every mountain and island were moved out of their places.

So, if that happens before anything in chapter 7, and beyond, happen, then please help me understand something.

How do the following happen "after" the stars have already fallen to the earth, and the heaven as already departed as a scroll?

Revelation 8:10 And the third angel sounded, and there fell a great star from heaven, burning as it were a lamp, and it fell upon the third part of the rivers, and upon the fountains of waters;

 12 And the fourth angel sounded, and the third part of the sun was smitten, and the third part of the moon, and the third part of the stars; so as the third part of them was darkened, and the day shone not for a third part of it, and the night likewise.

Revelation 9:1 And the fifth angel sounded, and I saw a star fall from heaven unto the earth: and to him was given the key of the bottomless pit.

Revelation 12:4 And his tail drew the third part of the stars of heaven, and did cast them to the earth: and the dragon stood before the woman which was ready to be delivered, for to devour her child as soon as it was born.

Does this all happen "after" the events of chapter 6 conclude?

Also, if the following, in chapter 6, is the day of his wrath, then will there be more days of his wrath in subsequent chapters?

Revelation 6:16 And said to the mountains and rocks, Fall on us, and hide us from the face of him that sitteth on the throne, and from the wrath of the Lamb:

 17 For the great day of his wrath is come; and who shall be able to stand?