You can either cry over Flipkart's delayed joining date.
Take it as an opportunity!
An opportunity to do what'er you wanted to do !
Think of it as 4 months of cushion!
GO see the world.
Because once you enter the corporate life, your dreams will fade away (let's just accept it!).
I'd seriously suggest you to startup/execute on an idea you are sitting on because even if you fail, you have a guaranteed job.
In fact, consider yourself lucky because you have seen this shit pretty early in your corporate career (you now have a story to tell your colleagues after 5 years).
Worried about education loan ? Don't be. The smarter you will figure out something - infact, 3 years down the road, this small issue won't even matter (by the way, the loan repayment starts after 6 months, so stop crying).
Take a chill pill. Come out of your IIM mode and do the do.
It's these moments that brings out the man/woman in you!
You belled the CAT. Now Be The Brave CAT (hope you get the pun) . But for god sake, please don't cry over spilled milk.