In order to be charged with a felony, don't you have to have imported more than the standard three month supply for personal use? Something must have really been amiss to have 15 members of the DEA task force and a drug sniffing dog in your house... As far as I know the dogs are trained to sniff out coke, weed and heroin. Certainly not any meds a person would take for a headache. Anyway, after the first Customs letter, I would have went with an "over the phone" consult with a US OP. More costly, but some are not that bad. Some of the pieces of this puzzle seem to be missing...
Need more info.