Oh yes, exp. dates are totally made up and if the prawns have been frozen at all they will last longer, maybe much longer than the stupid date on it.
Feel the meat, is it slimy? Yes, don't eat it. No, sniff it - does it smell like a dumpster. Yes, don't eat it, No it's fine. Now remember that raw meat does not smell good so it's always going to smell bad but rotten meat smells horrific!!!