Strange problem with my links…

Hey:
It’s like one thing after the other today. This is really weird though…
Once again, when I click on the posts title…the comment screen appears and everything is fine.
But when I go to click on any link in the horizontal menu up top, it redirects me to a page
that cannot be found…obviously something to do with permalinks or what not.
That’s messed up because first of all, those are links that I put into the page…they shouldn’t have
anything to do with anything? And why would these permalinks be messing up in the first place?
I’m I making sense? The links on the side menu are generated by WP, the links up top are mine.
M