I dreamed that I was in a sort of dungeon thingy, and me and a few friends had found this cool secret passage that you could only get into by tapping a certain combination of bricks on a wall, and so we explored the dungeon and it was all cool and stuff (can't remember details, just that it was awesome).
We went away for a little while, and then we came back and there was a huge goblin army marching out of the secret passage. The area in front of the passage had changed from a small tunnel to a huge underground amphitheater, and a bunch of my classmates were in the seats, preparing to face this evil goblin army. It was really quiet and everyone was scared, so I decided to take out my trumpet and play it to raise morale.
Unfortunately, I failed to play even the most simple thing I could think of, which was quarternote'G'-tie-halfnotehigh'C' (sounds like a generic Hollywood war-horn), so it obviously failed to raise my "army"'s spirits. Then, somehow, I managed to play the American national anthem flawlessly, without even having the sheet music for it, which is especially weird since I'm Canadian.
After that, I decided to arm myself, and realized that I could use the metal rod from my fold-up music stand as a weapon, so I go get the bag that I usually keep it in. Conveniently, along with the music stand, the bag also contained a wand of stunning and a knife.
Then, a goblin starts coming for me, so I zap it with my wand, sending it flying backwards, but it shakes off the stun and starts coming for me again, and then I wake up.