rejecting an accepted offer

So I had my first interview since my job search after returning from China last Monday and I had a good feeling I would get the job. It was an R&D scientist position in a sterilization testing company and although the position didn't really go with my career interests, I was applying to anything science-related that I could do b/c I am always hearing how bad the job market and was afraid I wouldn't get a job. But as I learned more about the position and the company during the interview, I felt a growing dislike of the place. They wanted someone permanent and not go to grad school either. I wouldn't have mind this b/c I know that you could leave whenever you wanted to, but I also wanted to use wherever I am working at to be a good reference for me when I do apply to grad school. So I was pretty sure this place would not want to be my future reference if they learned how uncommitted I was.

I would have learned a lot of stuff there tho and gain alot of skills in research planning, marketing, and leadership, but even if they would be a good reference for me, I still felt that this place was not going to let me develop my research skills in a physical chemical science field. So I get their call 2 days later and for some reason, I gladly accepted their offer. The call got intercepted mid-way, and I was already thinking of a polite way to turn it down but I couldn't think of it in those few seconds and I accepted it after our call got re-connected. They were expecting me tomorrow @ 9am.

After the call, I just entered a state of mild terror >.<  I am not good with my talking skills...blah. On the train ride to my school's career center to give in my revised resume (ironic already?), I kept going thru my mind all the diff. ways for how I would retract back my original statements w/o making myself appear totally unreliable and unprofessional or even just a complete liar. That was 2 hrs of stressful thinking and when I was finally facing a computer, that was when I realized that I could EMAIL instead of talking directly on the phone. I searched online and found that ppl even put up sample letters on how to reject an accepted offer. It took me close to an hour just to send a 5-sentence email -__-.......I hope he receives it in time, but I cannot express how much of a burden was lifted off of my shoulders.

I realized that I am REALLY REALLY stupid in applying there in the first place. I felt like I was diving-into situations head first w/o thinking more carefully beforehand. From now on, I am going to focus on applying to places that are more in line with my interests even if that means taking a long, long time......