When meat goes brown it means it's more tender/tasty. Chefs actually encourage you to go for brown steaks and not bright red ones, like most of us do, because the longer meat is "hung" the more yummier it is. But to make sure, smell it. I'm also overly funny about eggs and meat, I sniff everything and annoy my boyfriend who says "For god's sake, why do you have to smell everything" lol. You'll soon know if it's out of date by the smell when it's cooking.