If you could do ANYTHING in your life over what would it be????

Okay about a month ago I interviewed for this great job(or so I thought at the time) at a casino near my house. I wanted to do something different and make a little bit more money. I went to the interview, took the drug test, did the fingerprinting, the orientation, but when it came time for my first day of work, I couldn't do it. I was completely petrified of going into this entirely new world(to the point where I actually had panic attacks)and I blew my chance at this job. I guess you could say it's my fear of change-I'm highly afraid of this-that caused me not to do it. Now as time has ped I wonder if I've made the right decision.....and to ask how long do you think I should wait before I can re-apply? I realize my chances of being hired again are slim to none, but I don't want to spend the rest of my life wondering what if? My whole intention of going to get this job was to quit my other job.