I have this same problem. Phone conversations are very awkward and anxiety-provoking for me. Aside from my mom and brother, I can never talk to anyone without misperceiving when it is my turn to speak, or without drawing a mental blank when it is my turn to speak, or slurring my speech due to anxiety.
This is apparently a common problem for people with social anxiety neurosis.
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Autistic (self-identified)
Open source, free software, and open knowledge geek
GoLang, Python, & SysAdmin aspirant
RPG enthusiast
Has OCD, social anxiety, CPTSD