The question is, were you formally denied the visa (i.e. did they take your money)? I've heard people say in the past that often when you apply in person they will "reject" you (i.e. pretty much tell you you have no chance of getting the visa) without formally accepting the application... if this is the case then you should be ok to reapply straight away.
On the other hand, If they did take your money & deny your visa, I couldn't see that it would really be a problem... yes, they would probably look at your application in more detail (is there anything else you can add to it?), but at the same time if they look at it in more detail it could potentially be a good thing...