How many times can I use my Warranty to repair a product?

Hi. My computer, which I just got yesterday, keeps having problems when i turn it on but the computer screen stays dark. I will be sending my computer in for repair at dell. Is there a limited amount of times in which I may use this warranty? Also, is it possible to cancel the already placed box shipment and have a technical member from dell repair my computer on site?

I have the:

Next day business support (expires oct 1, 2015)