Qualifications
See that "Dr" in front of your name? Yeah—you're going to have to earn it.
You won't need to obtain a PhD to practice, but you'll need it if you want the "Dr" prefix. However, at least a master's—in either counseling or marriage and family therapy—is a must (source). We humans are complex creatures, and there's a lot to learn about all of our ins and outs (source). Actually, concentrate on the ins. Leave the outs to the doctors who are licensed to operate a scalpel.
After you have your degree, you'll need to have two years of supervised clinical experience before you can become licensed. There'll be an exam issued by the state that you'll have to pass, and you'll have to take continuing education classes thereafter. In that respect, you'll never be done with school. So don't toss out your Transformers lunchbox just yet.