|"I accidentally dropped my Dell Latitude D531 laptop on the floor."|
Dropping a laptop often results in something getting damaged inside the laptop.
Take it to a local laptop repair place that is autourized to work on Dell computers and have them analyze it.
Damage caused by dropping it is NOT covered by it's warranty even if it's still in effect, unless you bought additional warranty coverage that covers accidental damage, when you bought the computer, or within a short time (e.g. 60 days) after you bought it.