Can takin stimulant laxatives cause a positive drug test for methamphetamines?

Last thursday I took 3 over the counter laxative pills (generic for ex-lax) On friday I was required to take a random drug test for my probation. This is a regular thing and i often have to go more than once a week to drop my pee off for testing. All my tests have been negative since I've been on probation and I've been clean from drugs and alcohol for 15 months. However when I went to court for my monthly check in with the judge my probation officer pulled me aside before court started to tell me that my last test was positive for methamphetamines (trace amounts) Could the laxatives have caused this false positive?

: http://alcoholdrugstreatment.info/can-takin-stimulant-laxatives-cause-a-positive-drug-test-for-methamphetamines