Given the sensitivity, absolutely nothing. Seriously, a negative only means that the sample swab didn't have COVID on it. This test is not very useful unless you get a positive.

For context, my wife is a physician. Had a patient that turned out to be positive, test negative while in the hospital. A day later, he was intubated. While he was intubated, his original, outpatient, test from 11 days earlier came back positive.

This test is mostly useless anyway: you need to administer it at the narrow window when you have covid for it to be effective. This implies that you have to keep it on hand, ie it can be too late to order it when you have symptoms since it can be delivered too late to detect anything. Then you have to wait for results for many days once you send it - so it’s useless for guiding your action during the time you have symptoms.

If you administer the test when you don’t have symptoms it useless as well since most likely you will miss the window.

Not sure why you would take it if asymptomatic (assuming you aren't an essential health worker), unless you were told to either as part of a random sample study, or because a contact tracing effort told you you were at risk.

If you take it while symptomatic, I believe the sensitivity is improved, so if it comes back negative, you can be pretty assured that you just have a regular cold, right?

That'll you need more testing through the rest of the pandemic until it's either over or you come back positive.