Recover "Broken" Raid 6

Hi All

I need some assistance from our Raid Gurus...

I needed more space, so i expanded my rail with mdadm and add one more 2TB drive to my 10x 2TB Raid 6. Raid was in "clean" state.
About an hour later i noticed that the raid has gone to "degraded" and that two drives show up as "removed". After doing some checks, i found that one was a drive failure and the other one was the new drive i just added. I replaced the faulty drive and added the two drives back with as follow:
mdadm --manage /dev/md0 --add /dev/sda1 and mdadm --manage /dev/md0 --add /dev/sdb1
i did a check - mdadm --query --detail /dev/md0, and it showed up as all 11 drives synchronizing and i left them - took two days - to complete the Sync.

This morning i mounted the drive, but i am unable to see any data???
I also checked command df and it shows that my drive is empty... Did i just lose all my info or is there ways to check if the "index" file is not correct or if i can re-buid the index file ?

Any assistance will help at this stage.