You might be lucky !! Because you could return your apple product within 14days prior your purchase
Although you have open and used your mac. You still can return it with 2 reasons: First you are not satisfied with your mac and second you feel a new macbook is much better and would suit you best.
Apple usually grants you with the exchange, although the retail may not, I would suggest you call Apple care directly as they have power to exchange it for you !!! (I did it before cos my retail didn't allow me to return my iMac but the headquarter allowed me to)
Here are the policies on the Apple website:
Return and Refund Policy
If you are not satisfied with your Apple purchase of a product, please visit online Order Status or call 1-800-676-2775 for a Return Material Authorization (RMA).
Items in your order will be divided into two groups items that are eligible to be returned online and items you cannot return. For each item that you can return online, you will need to select the item, a reason for return, and whether youve opened the box. Well provide you with an estimated total refund amount less restocking fees, as applicable. Youll also be able to print a return shipping label to place on the box you use to return your item(s).
Once youve submitted your return request, youll receive an email confirmation with your return details. You are responsible for shipping the items back to Apple, including shipping fees. If you have multiple items to return, you may put them together in one box with the packing slip. We strongly recommend using the original packaging if you are returning a computer.
Items(s) must be received by the Apple returns center within 14 calendar days from when the return was requested.
Once we receive the item(s) well process the return, issue a refund, and send you a return receipt confirmation email.
Good Luck !!!
