What is the normal time it takes..?

For a person to learn an office managers job. This includes accounts payable, receivable, pay application, payroll, tax certificates, certified payroll, lien waivers, plus answering the phone, doing all the mailing, running to the bank to make deposits etc getting notary signatures plus reconciling 2 bank accounts along with keeping up with 4 credit cards? I have had 2 weeks training and the boss does not understand why I have not picked all this up and running smoothly? I am beginning to feel stupid. Keeping in mind he (the boss) is a neat freak and requires everything to be tidy including MY desk in MY office all the while he keeps giving me more tasks to do all the time.