During a very scary situation it is a normal human response to be suprisingly calm. I think its a helpful adaptation so that we can deal with a lifethreatening crisis, so we can still think and act where panic would stop us. Think of those moments where you think "oh, the car is skidding, I'd better not brake" and then later you experience the fear.
We are also calmer if we have practiced the response, in theory or actually done it eg the skidding analogy.In maternity, we practice for baby resuscitation and, of course, PPH, amongst other things. Maybe the mw was trying to slow, and calm, the reg, so that they could follow their local drill together.
I had a client who had a major PPH and woke up in ITU. She was a nurse so knew immediately that something serious had happened, yet felt really calm. Thinking, well, I feel ok, so whatever was wrong must now be sorted. Then the consultant came to see her. He got emotional when explaining what had happened and that made her connect with the scariness of the situation for the first time. It was only then that she started to feel upset.
I think when you have a debrief, you should also involve your OH. His memories will be different and his fear at the time for you will have been very acute. It can cause a problem for couples if they are unable to discuss a scary birth and acknowledge how each of them felt, and feel about it now.