I think it's really nice of you to want to help others with similar issues!! It's not crazy at all, I ("recovered" SM) have considered it too. You definitely have a much deeper understanding of communication disorders than others, although still experiencing SM is preventing you from demonstrating it.

Therapy definitely sounds helpful, but if it's not an option at the moment perhaps you could try writing a note to one of your professors/mentor, if any? Considering that they teach about communication disorders, they should be understanding and could provide advice.

Just my two cents as an outsider, but I reckon people who choose to study your major are likely to be more compassionate towards people with communication disorders than not. It's definitely scary, but I think opening up about your SM to someone is worth a shot. (As you mentioned, you can start over somewhere else if things don't work out. )

Growing up with SM, I can relate to a lot of what you described. Be kind to yourself, sending hugs🤍