Everything is very individualized and there are many factors that will effect your response to treatment. A good ball park for a simple problem is at least 50% improvement within 2 weeks of consistent treatment. Response may take longer for more complex issues.
No. While we see many patients in the clinic who are referred from their Medical Doctors, a referral is not necessary. Similar to a Dentist, Chiropractors are primary health care providers, able to evaluate and diagnose issues on their own.
That's a bit of a loaded question! The simple answer is yes. Multiple research studies have shown the different treatment modalities Chiropractors use as safe and effective help for muscle, joint and nerve problems.

Everyone has heard stories about Chiropractic manipulations causing injury, but the most recent and best available evidence tells us the vast majority of “Chiropractic side effects” are minor soreness or stiffness related to hands on treatments. Those severe stories are likely problems that started before ever seeing the Chiropractor and were likely progressing on their own.
No, our goal is to always have people leaving the clinic feeling better than they did on the way in.  That said, in some cases, because the area in need of treatment may be quite tender there can be some discomfort in treating the area.  We can adjust the intensity of treatment to minimize any discomfort, but sometimes that equates with slower results.  The goal is to find a balance and provide treatment with minimal discomfort and maximum results.