My administrator account was set to standard?

So I just got a brand new macbook pro about 4 months ago. It was working perfectly, until last night everything froze and stopped responding, so I restarted my computer. But when it restarted it took forever to reboot and when it finally did it just gave me options to restore with time machine, reinstall os x lion, check my disk for problems or search for help. After trying to get all the other options to work (none of them did), I opted to reinstall os x lion (wasn't too worried about losing files or data or anything seeing as there wasn't much on here yet anyway).

So the reinstall seemed to work fine. All the mac basics were there and stuff and some of my files had even been recovered. But when I tried to reinstall an application I had lost, it asked me to enter the admin information to confirm that this was ok. When I entered my username and password, it didn't work. I tried multiple times and it kept not working. So I checked Users and Group settings and sure enough, my account (the only account that exists on this computer) is set to standard! So now my computer has no administrator account. Obviously, I need one to reinstal all my apps, so please help? D: