Christmas eve advice for a backpacker thinking of flying in to Germany

I am currently in Mumbai, India but am thinking of spending the holidays in Germany.

Problem is:

A) I don't know anyone there

B) I am thinking of flying in on christmas eve.

C) I don't know how difficult it would be to find a hostel or room for rent.

I'm not even sure if grocery stores will be open or how limited my food options will be.

Will I end up starving and freezing to death in a ditch or are there places that I can go that would be accomodating to my situation?