I don't think you internalized your fears, I think you very successfully redirected your energy.
Exactly what I was going to say!
There is a difference between bottling up in a negative way and redirecting your energy to help yourself stay calm and focused - and what you were doing sounds like the latter.

While some women find yelling and screaming therapeutic I think most women who manage labour well (at least from what I have seen) eventually settle down, become quiet and really start to concentrate on what they're doing. When they get to this point they often tune other things out, which is why it's interesting that you said you didn't want anyone talking to you. Touch and eye contact and other non verbal stuff starts to become more important. When you find something that works just do it, don't worry about what you think you're "meant" to be doing.

Wow not too long to go now, good luck I'm sure you'll be awesome!