Why can't I get a job?

I'm posting this under the gay section of Answers because, honestly, I think the reason might be because of my sexuality. I was a very good student. I had a 3.7 GPA in Economics. But after college, I found it impossible to get a job. I went to a very good school, and all the people I went to college with got good, professional jobs that paid six figures. But the best I could do was a minimum wage job as a cashier at a grocery store, which I got fired from because I would get too nervous to count accurate cash. I felt like such a loser. Could employers be rejecting me because of my voice? I have a high-pitched, effeminate voice ("the gay accent") that people have made fun of me for my entire life. In high school, I even developed a phobia about talking because everyone made fun of me so much. I just stopped talking in public altogether. I hate my voice, but I really can't change it. My mom works in a hospital, and got me a job that's a step above minimum wage as a secretary. I hate it. I feel like I'm too smart to be working a job where all my coworkers are high school dropouts. I'm going to be doing volunteer work soon at my city's Gay Center. Could that lead to a paying job? I figure it's probably not a bad idea to surround myself with some people like me.