Macbook stuck on prohibitory page

I'm using Macbook Pro 2012 running Mac OS X 10.10.3 and earlier today, I was trying to install Linux on a USB drive through Terminal.

I first converted the format with this:

hdiutil convert -format UDRW -o ubuntu.iso ubuntu-1xxxx.iso

Next, listed drives with:

diskutil list

Added my flash drive.

And then ran this: diskutil unmountDisk /dev/diskN, where N being the no. of drive from the DiskUtil list.

Here by mistake I chose the disk0, my boot recovery in my opinion, and unmounted that.

After that I ran,

sudo dd if=./ubuntu.iso of=/dev/rdiskN bs=1m

, where again N being the no of drive listed in DiskUtil list. Here again, absentmindedly I chose disk1, the Macintosh HD, in my opinion. And suddenly after that I realized, what was happening and cancelled the process midway.

After that I tried remounting my recovery, but my Mac froze and after I tried to restart i got stuck at the prohibitory page.

I tried booting into Recover with Command+R, and tried mounting my Macintosh HD from there, but it gave me a error, that it couldn't be mounted. It asked me, to check a Disk Verification and Disk repair, I did that on my Macintosh HD and both were okay.

But after that also the problem persists and I can't mount the Macintosh HD and still stuck at the prohibitory page.