You also need a referral for MRI from the GP here. Mine referred me, but 2 days later, I was in hospital, and they did all the tests immediately. Can you ask to see another GP to get the referral? Don't feel guilty for asking for tests and support. You want to find out what's led to a sudden change in your speech. If you're in the UK, I have heard the wait for speech therapy is long. I kept on at the GP, and I made complaints about their lack of care. I had my first appointment this week after the referral going in in May. Good luck.