Why is my flash drive saying the volume is dirty?

[Sixtrock]

My laptop has been A LOT slower than usual, and a lot of the pages on the internet don't respond. I'm thinking it's a virus, and i would like to know what you think it could be, and what i could do to prevent further viruses, and "cure" this one? anything can help thank you. Oh, and when it doesn't respond, the screen goes like white, but you can still see through it, and it makes this low beep noise? parenting tips how to stop procrastinating daily motivation overcome shyness stress reduction improve concentration the power of your subconscious mind