I feel I am under-qualified for my job. What to do?

Honestly I would approach this problem like this. The accounting of this business was flawed from the beginning, therefore even if you had inputed the correct data you could not possible produce the great reports your superior is asking for. I'd note this in some kind of summary or make a notation why there is a discrepancy. Now from this point forward I would input everything, both in a spreadsheet and in a general ledger, not to mention to keep separate records for each account, reconcile the accounts often and double check your work. I don't think you are under-qualified for the job, just lack experience. Think of this as your opportunity to learn hands on. I went to college for software engineering and am often wonder if I would be under-qualified to work as a programmer. Also maybe you should take in consideration how much you are getting paid. Most accountants get paid salary and not hourly. Good Luck