Esmi
I should share this with all fellow wordpress user.
when we upgrade to newer version-we get scared very easily if certain features does not work. I am advertising my website on facebook/google now, so for me getting my site back is very important.
So i downgraded and uploaded my customized css and php files. Once i did, i found that media files are not working again. Then I checked the php files I changed recently and voila! by removing that link it worked again.
I upgraded again back to newest version.
I really learnt a lot today.