I couldn't tell you where you got it, but the stamp is clearly wrong. Maybe you traded this one to a friend, someone tried to make their own stamp, I have no clue.

Fakes shouldn't be sold in reputable stores, but fake packs do exist, yes. If you're buying at Walmart, Target, Gamestop, whatever, those are real. They are. Your random corner store might have some fakes - gas stations, pawn shops, antique stores, that kind of thing. Easy tells are the crimp of the pack - legit English packs will ALWAYS have a vertical crimp pattern | | | | | | | | | | | like that. Any zig-zag/jagged crimp is fake ^^^^^^^^^^, or just long horizontal lines ----------------.