Would one puff of crystalmeth show up on a urinalyses if they test for amp?

Yes, one puff of crystal meth (methamphetamine) can show up on a urinalysis test that screens for amphetamines. Methamphetamine can be detected in urine for several days after use, depending on various factors such as metabolism and the amount consumed. Standard drug tests typically look for the presence of amphetamines, which includes methamphetamine.