Getting a head shot can sometimes be intimidating. This is what you're going to be applying to jobs with and this is, sometimes, the first impression someone has of you. Having a clear and professional portrait is always a plus and good sign to future employers that you're serious and willing to put forth your best for them. It's showing them you're a professional before ever working for them!
I know it can be scary and that you don't want to go to someone and be disappointed. My head shots are always done within my studio and I always try to stay in contact with my clients before they ever come into the studio to help with clothing and selecting the perfect backdrop. Everything matches and looks flawless. I always encourage splurging a little and finding a make up artist here in Charleston, SC before your headshot! Pamper yourself and really enjoy the process :)