If your eggs are bad it'll become immediately obvious.
Best before dates don't mean anything, they're a random guess, depending on how the food is stored and a whole host of factors no one can pinpoint a date when it'll go bad. Use you senses - sight, taste, feel, smell. It's not rocket science man.
In the fridge eggs last a long old time (although it's less than ideal to store eggs at low temps in terms of usability and cooking, you're better off at room temp). I imagine they'll be fine, if they aren't it'll become immediately obvious upon cracking due to the smell.