Something weird

[lina <lina.lastname@gmail.com>]

Hi,

When I browsed some website, 
 Just for a while.  
I did not notice the screen.  

The iceweasle moved over screen.  I can't clink the small, enlarge or shutdown button 

Neither can move it.  Same for the terminal.  

All started from the file edit view line at the top of screen.  

And the terminal has no reaction.  Only an empty square after 
lina@debian:~$ 

The only way I can use is the press F1.
F series keys.  

Any idea how to check? Or what I have done wrong? 

I restarted, still the same.  

Thanks 

It's wheezy with xfce 4 

Lina