Okay. First off, this represents my opinion. I'm not a famous writer or whatnot, but these are my two cents. Annoyed? R-mail me, don't post here complaining. :/ 

(Paranoid about people disliking my post :U Doesn't apply to you Wish)

Lol'kay. Won't be a very long one then. o3o

I'll just start by saying you are comma-happy.

The theme park of absolute danger, unexpected
results and well, you'll
see. But if you put this book down, you
will never know what happens to me, and
my precious life. The world as you know it depends on you finishing this book, also
known as my journal, my
head and reality.

That's six commas in three sentences; while not
overdone your sentences are also wordy, so they don't fit well together. I'd
try re-writing them as separate sentences, or just remove some of the stuff
that isn't needed.

The park of absolute danger and unexpected results;
well, you'll see. But if you put this book down, you will never know what
happens to me. The world as you know it depends on you finishing this book.

In my opinion it feels as if the other words are
just fillers. You don't need them and they add little to the overall paragraph.
If you want quantity, I'd think about the quality at the same time. You can
tell the difference between 'padding' and actual information.

--

Then there's awkward sentence-structure, something
you would want to avoid. Missing words, run-on sentences and sometimes you just
have repeating lines. For example:

If you have not guessed, these pages hold my life. From
age who knows what, to now. And
it soon will hold the future, if you want it to. My
name is Pen. Penelope Kane in full. And
I am pirate. Flesh and blood pirate.

Right, so. Blue is repetition, orange is
unneeded/incorrectly written/missing words, and green is structure. Or
something along those lines. LOL

-This is repetitive from the beginning paragraph.
If you keep it as it originally was, you are repeating the fact that the book
is about her life. By now, we get it. In fact, in the original first paragraph
you allude to it twice. You can consider taking this out entirely or replacing
it with unknown information.

- The first sentence highlighted, 'From age who
knows what, to now.' makes little sense. If this is her journal you
could easily give us a starting age, but if you don't want to just try
re-wording it. 'From age who knows what' is awkward and
doesn't flow easily, if you try reading it closely. Substituting it with 'from
my childhood' or something that relates to a young age may work
better. The next line, 'And it soon will hold the future, if you want
it to' is more or less useless to the rest of the paragraph, in my
opinion. The 'if you want it to' may also be unnecessary. Something more
graceful might be 'And soon it will hold the future', since the
word order in the front is also somewhat awkward. Last line; 'And I am
pirate. Flesh and blood pirate' First, you're missing the 'a'. A bit
crucial, that is. And in the second part as well. 'And I am a pirate; a
flesh and blood pirate'.

- Lastly. This is fine to leave alone, but at the
same time, it's uninteresting and dull to read. The more excitement
and action in the words the more hooked a reader will be. 'My name is
Pen, Penelope Kane'. You can play around with it, really.

Just remember these 3 words. Never. Give. Up.

Rather than using the numbers, try using the actual word forms: 'three'.

Just remember these three words: Never. Give. Up.

There's more, but I can't concentrate. D: I'll type it up later.