Selective mutism - anyone have experience of it in adults?

[selectivelymutemaybe]

I'm wondering if I have selective mutism, as I have a lifelong intense shyness that I've not been able to outgrow. There are lots of situations that I have learnt to cope in from necessity, and I have some kind of internal hierarchy of who I can talk in front of and who I can't.

Today I had a meeting with 5 peers and a senior professor. I spoke freely with the 5 peers, and then as soon as the professor showed up I couldn't speak and I was struggling a lot with just maintaining eye contact. I literally could not speak, even though I knew it was probably giving them a poor impression of me, and was hindering me as I could have asked some questions on things I needed help with.

It happens a lot and feels like a physical block in my throat stopping me from speaking. I can nod and smile but cannot speak.

I'm not sure what to do

Do you have the same reaction to anyone in authority? Could it be a fear of failure? Or imposter syndrome? That must be very debilitating for you, especially when you are aware. Write out a list of questions and read one out to someone like that, rather than make eye contact. Would that help?

It's not really just authority figures, as I'm ok with some and not with others. It's highly context dependent. I hate it.

In my previous job the head of department pulled me to 'go for a coffee' and it was essentially them tell me I was too shy and to start being more confident. It was so humiliating.