He had meth in his system because he was smoking meth. The fent, he swallowed during the traffic stop. Remember that the clerk who called the police was barely concerned about the fake $20 bill, but was far more concerned that he was acting insane and saw the dude driving erratically. But yeah, if you look at the coroner's report, Floyd had 11 ug/dL of fent in his blood, which is higher than in 70% of all recorded fatal fentanyl overdoses, BUT he only had 5ug/dL of norfentanyl, the metabolite. Usually you would have a lot more of the metabolite than the drug in your blood, like 20x more, which means he just ingested it. Him complaining about not being able to breathe when he was still in his own vehicle and refusing to get out was because he knew that he just swallowed a fatal amount of drugs and he wanted them to call an ambulance to give him some narcan and turn fatal into literally nothing. Turns out that it takes longer than normal to get an EMT out when it's Memorial Day and there's a global pandemic going on.