good advice from posters above. please google about wordpress security - especially if you install manually. use a plugin like wp-security-scan to look for holes.
you could have started with a free host that offers mysql, just to get the hang of it.
two more things noobs get caught in sooner or later:
- check your hosting plan (the small print) - you might have a limitation on your number of files, make sure to disable the catchall e-mail account to avoid reaching that because of spam
- backup your content and settings religiously - if you don't start with good practices it will be increasingly hard to develop them later (and expensive, since you'd start looking at this *only* after losing precious data).
Good luck!