How long is the statute of limitations on a drug charge in Pennsylvania? 1 Answers as of February 21, 2012

While in a car driven by an acquaintance we were pulled over and asked if the car could be searched, when the driver said no they brought a k9 unit and the dog barked our whatever, so they took me and another defendant to the station (excluding the driver?). Anyway they questioned us extensively and made us sign there papers with our answers on them,(stupid of me I know) and at the end said I was not under arrest and that this was part of a larger on going criminal investigation and that they'd be in touch, one of the police even gave me a ride back to the town I live in. It has been 2 days less than a year since then and I have not been charged with anything, can they still charge me?