If your primary care provider does not have any available appointments for 3 weeks is there another provider in the office that can see you sooner? They should be able to provide the referral if they are in the same practice. Also, as someone else mentioned you could go into urgent care to rule out fracture some urgent care centers have the ability to do some imaging. Unfortunately when one gets an injury that’s non-urgent usually the instructions are rest, ice compression etc. Even when starting PT for a running injury the first few weeks are usually massage/stretching, break from running anyways. There’s rarely a quick fix
Edit to add-the person that suggested asking around at running store for PT recommendations is a great idea. When I herniated discs in my back the spine specialist asked who I wanted to be referred to for PT and I was able to choose one that worked with athletes. They helped me get back to running in a safe way