I began to walk again and decided to test a theory. You know how it's difficult/impossible to shout or scream in a dream? Well, I tried this several times, and I felt how the sound caught in my throat. Then I tried to sing a note as loudly as I had intended to shout - and that sound came out fine. I tried this several times. High-pitched and low-pitched sounds at high volume, and all came out great.

So, dreamers: if you can't shout in a dream, sing instead!