Last words from CVR (We are falling, sir) in explicit way suggest loss of control. However, it still could be from many reasons like stall, upset, structural failure, etc. We know nothing at the moment about critical event.
And, IMO, its very unlikely that they retracted flaps instead of landing gear just after airborne.
Should be an audible alarm noticed then. But it wasn't.
And finally, Head of the russian FAA said clearly that except last 10 seconds everything was pretty normal in that flight.