My mom thinks i do drugs because i'm disorganized. she wants me to take a test. i've never done drugs. is it possible that it could show up positive?

Yes but unlikey: Depending on the kind of test, there are several things that cause a positive test besides the drugs being tested for. Any test needs to be interpreted by someone who understands this.

False positive rate: The false positive rate (= test says you have taken drug x when in fact you haven't) is about 5-10%, depending on the test. There are a number of reasons for this, such as if you take certain medications (either over the counter or prescription). Eating a large amount of poppy seeds can give false positive. Given these caveats, the test will be negative 90-95% of the time.

No but...: Certain prescription drugs or otc drugs may give a false positive test. It is important, therefore, to list all the medication taken recently to avoid confusion.