If im prescribed adderall but used meth and had to take drugtest how can I pass gcms?

Okay, this is funny cause as of today im in the same boat as you. I have been taking Adderall for 4 months 20 mg a day so my PO knows i test positive for AMP on my drug tests. Last night at 8 PM my brother bought a gram of some good crystal and i have never done it. Basicly we tweaked from 8pm monday night to 10 am teusday morning. Im thinking that once the meth is ingested it metabolizes down to AMP (amphetamine) so i think we might be good. but maybe if we team up an help each other we can be sure!