PROBLEM After Installing KALI LINUX on MY LAPTOP WHICH Has NOW AFFECTED MY WINDOWS 7 OS (I Wanted to Dual Boot Kali Woth

Hello

I have been reading on null byte a lot.

So i wanted to dual boot kali linux with my windows 7 as to try all the hacks in the forum, i installed kali from a usb drive, but a MAJOR problem has occured

I foolishly selected "Guided:entire disk" while installation.

Because rhe Kali live was not working and i was unable to use gparted like software.

Now i didnt installed grub in master boot loader and wanted to install it on a Usb but by mistake i pressed enter without writing the device name and all.

I configure any package and skipped the stage i tjought i would add it in the " source:list" afterwars. And the installation finished successfully.

BUT NOW A MAJOR PROBLEN HAS ARRIVED WHEN I TURN ON MY LAPTOP I DIDNT SEE OPTIONS TO SELECT OPERATING SYSTEM.

AND KALI IS NOT WORKING.L, IT SAYS THAT -" media test failure,check cable" and "exiting PXE rom" and page changes and then next it says non system disk or disk error replace and strike enter.

NOW WHAT SHOULD I DO. I WANT MY LAPTOP BACK WITH WINDOWS 7 OS back IN IT. I WILL USE KALI WITH VIRTUAL MACHINE. PLEASE HELPPP MEE.

P.S. MY LAPTOP'S CD/DVD DRIVE DOESNT WORK.