I'm having the exact same problem right now!! In fact, this happened to me yesterday in chemistry! HaHa Music always helps me to calm down or concentrate. Here is a pretty good mix that should both relax you and help you to concentrate. Good luck! 
 
http://8tracks.com/awgg919/music-tha...nt-to-study-to
 
		
	
		
		
                
		
		
			 
            
              
            
				Stay Strong.
Message me if you need to talk. I may not always have the best advice, but I'm always willing to listen.
Aim for the moon for if you fall, you will land amoungst the stars.