There are no Georgia state laws specifically relating to overtime. Instead, the state relies on federal laws regarding overtime to protect workers within the state.
For covered employees, a "workweek" means seven consecutive days. For example, your workweek could be from Monday at 9 a.m. to the following Monday, or it could also start on Wednesday at 11 p.m. and run to the next Wednesday.
When the workweek begins does not matter, in the eyes of the law. All that matters is what happens in the following 168 hours, meaning the seven consecutive days. If you work more than 40 hours within one 168-hour period, then you are entitled to overtime if you are covered by the FLSA.
Some employees are paid by the week, some biweekly; some get paid once a month, but none of that impacts your ability to get overtime. Overtime is still based on how many hours you worked in a single one-week period. Working 60 hours one week and then 20 hours the next week does not "average out." You are still entitled to overtime for the 60-hour week.
Normally, you should receive any overtime pay due you on your next payday, when you would be paid for the rest of your time.