Inconsistent Paragraph Spacing - Apple Pages.

I am writing a text document in Apple Pages. When I begin a new paragraph I like to indent manually by 4 spaces, like this :

"Example of text."

"Example of text," showing indent.

Example of text not written as speech. Example of text not written as speech. Example of text not written as speech.

However, frustratingly, from time to time Pages decides to indent further, and I cannot figure out why, or how to stop it from doing so. As a result, I end up with inconsistent paragraph spacings, like this :

"Example text indented as I would like it."

"Example of incorrectly indented paragraph that Pages annoyingly decides to give me."

"Example text indented as I would like it."

This appears to occur randomly, and it is extremely frustrating, particularly in a large body of text with a lot of speech requiring suitable formatting.

Any help or assistance would be greatly received, as the document I am working on is around 50,000 words and I may just give up and go back to Microsoft Word soon,

Many thanks in advance,