Having problems with this one person should I trust sending?

I have a ps2 for sale and was contacted from a person that lives in Kansas. ((That is if she really does)) she was going to pay for shipping and all of that. It was for her cousin that lived in Kansas which later on I find out is in Nigeria and her fedex account has to be reactivated. I made a paypal so she could pay me she sent an extra 100 dollars okay thats cool, however the shipping is the amount she gave in as a whole for it to be expressed mailed. I am having a headach and the money isn't in the account yet should I just cancel? I had it on cragslist to be sold in my area.