So it's not like cheating or anything to have parts of the novel/characters planned out?
Definitely not. Remember, the only person you can cheat is yourself.
There are some people in NaNoWriMo who post 50k+ words on the first or second of November, and it's pretty obvious that they've already written most of their novels. I mean, realistically, no one writes that amount in a day or two. My attitude is the same towards them as in the previous paragraph: if you cheat on this, you're only cheating yourself. After all, the goal is to write your 50k words during the month.
As I see it, setting the groundwork in place before you start writing isn't cheating, it's homework or preparation. Obviously you should do the actual writing during the NaNoWriMo.
Did you finish your story at the 50k mark, or did you go over?
On the 29th of November, according to my records, I had 44.8k words, and after 11 hours of effort on the 30th, got this up to 50,745 words. I then spent about half of December finishing the story off, ending with about 61k words. Remember that in NaNoWriMo, no one checks on what you've written, so it really does come down to you, and whether you want to cheat yourself.
On the spreadsheet which is really worth grabbing if you want to chart your progress, you enter the Total Word Count, plus the number of hours you wrote each day. You get a heap of statistics, plus predictions on when you'll finish. When I was going for it, I realistically produced some 400 to 500 words per hour.
I was really fortunate in that the aforementioned author whose characters appeared in a cameo role in my story suggested approaching her editor for assistance (one of the characters spoke in a peculiar accent, and this editor was really good at helping with that). So, every few days, I'd send the story with a further five or so chapters, and so I received ongoing corrections and feedback. That really helped me, too.
ohh.. and I kinda realised I caused everyone to go off topic in this forum.. sorry about that :P
This is people writing about the longest stories they've ever written, albeit during NaNoWriMo. Yes, it's at a tangent to the original posting, but I don't consider it off topic.