If eBay is showing that you've been paid, it means that they've received the funds from the buyer. They'll then deduct their 12.8% of the total price (including shipping) and send the remainder of the money to your bank within 2 working days. (i.e. by Tuesday in this case). With the vast majority of High Street bank accounts that will probably mean that the money will the be available to on that day but a few bank accounts might still have 'clearing' times of up to 4 days.
NB: If you'll no longer be using your PayPal account, remember to close it, as PayPal now has a £12 per year 'inactivity fee' (for accounts which haven't been used in the preceding 12 months).