Help!? Looking for a job at age 17!?

Hi so I just graduated high school and I really need a job to pay for a car that I need to get to college this fall. I have already seen my schedule and some days the bus is not an option. I will also need to pay for gas and possibly insurance if my parents dont. My dad is already taking out a loan for the car, but I have to pay him off. Luckily I won't owe interest or have late fees because he is my dad, not the bank. I also might have to pay rent when I'm 18 (sept). Anyway, I have a resume with some volunteer work, but I have no actual job experience. These days under 18 and no job experience are big no no's so it's been really rough. I have had one interview so far but I was really nervous and blanked on things when the guy asked me questions (I can't help being nervous). I never heard back from this guy.. I have applied to a few other places with no luck. Today I'm doing another run to drop off about 8 applications on upper state st. (I have to get around on my bike). I'm trying my best but it doesn't seem to be enough. One of my friends in the same situation just walked into a place and they gave her a job after she asked for an application (same place told me that they weren't hiring). I don't come off as irresponsible or unkept, I actually come off as really mature. I guess I'm just asking for tips, I don't understand what I'm doing wrong. (Yes I dressed nice for that interview)

also I don't want to work at McDonals or stuff like that..