I wouldn't worry at all Best before dates are deceiving, it's to cover the manufacturers. I eat stuff which is ages out of date, if looks and smells OK then it probably is. Your juice is only just over a week out of date, it will be fine!
I've found with fruit juice and many other similar products if it tastes OK then it is, before the dates that was all we could use, and I've had some weeks beyond the date (as I live on my own so can't get through it in time) regularly and unless it tastes funny (it never does) it goes on and on.