The short answer is No you can't. Scammers from Africa are rife on eBay and it's a well known thing for them to pay for goods through Paypal with stolen or cloned cards.
Change the passwords on your PayPal and eBay account and anything that uses the same password, it's a very real possibility that the email didn't come from PayPal and as such you have just provided them with your details.
Quite why you sent a parcel without being paid up front for it is beyond me though and in that respect you're asking for your money and goods to be stolen.
eBay do have a refund scheme, but it only pays the first �105 and they charge you �15 for it and if you sent the parcel first then you may not be eligible for any compensation anyway.
Sorry to be the bearer of bad news