What does it mean if your acth level is low but normal cortisol? acth is 4.9, cortisol total is 8.9 and cortisol free is .33

ACTH/cortisol: These sound like normal values, but the most important question is "why were these tests done"? ACTH and cortisol bounce around all day long, generally higher in the AM. Because they bounce around, isolated values don't mean much. If your doc thinks cortisol is low (Addison's) or high (Cushing's), then there are provocative tests that are better.