But if you haven't given them payment details or paypal account how are they making payment?
I don't know if they have or not, but they will need something to make payment. Also I am pretty sure, I haven't used paypal to recieve money in a while as paypal are very crooked, but a payment made will get notification to the recipient pretty quickly, its a card transaction so should done in a few hours at most.
It's worth checking just to be reassured.
Jools