I don't think you should explain your hair unless the interviewers bring it up, at which point I'd take a "thanks for asking" approach as though they've just given you a compliment.
It's a fine line between explanation and excuse. As an interviewer I can tell you that while a nontraditional 'do wouldn't put me off, an unsolicited disclaimer might.
And speaking of unsolicited: there is no interview that can make or break your life. NONE. Academic, athletic, professional, personal, doesn't matter. Took me years to arrive at this conclusion, but at my advanced age I'm happily aware that failures and blown opportunities are some of the best things that've happened to me. The people who haven't failed, and failed big, I don't want to know. Pussies, all.
Still, good luck with the interview!