There's no hold on your paycheck. You are not paid the first week you work until payroll verifies hours worked and, if you are paid weekly, you will get that check the following week. If you are paid biweekly, it could be up to three weeks before you see your first check. It's all in how payroll defines the work week.
How long does it take to get your first paycheck?
Normally, you will receive your first pay check three weeks after you enter on duty according to the Department of Justice in the United States. I checked the Internet. It says that payroll checks may be issued at the end of each pay period worked.