How long does very mild to mild hepatitis last on blood work to show you had it ? ty

It depends: Why do you ask? The enzymes can drop to normal at any time. To tell if you had / may still be carrying hepatitis B and/or hepatitis C, check for the antigens / antibodies. These are very reliable. In a young man like yourself, the most common reason for having the enzymes up is a boozy weekend, or being fat / out of shape. If they stay up, get to the bottom of it with your doctor's help.