I am a 1. c4 player most of the time, and lately I ran across this unusual opening. Does this position/opening have a name?

That isnt the queens gambit.  It's the benoni defense (transposed).  b5 doesnt have a name.  I dont think it's very good.  You can just take the pawn and have a good position, a pawn up. 

Thats an attempted transposition to the Benko Gambit I would say. 

(If you play 3. d5 Nf6)

1. d4 Nf6 2. c4 c5 3. d5 b5

d4 is a bad move. c5 isn't the queen's gambit. It's the symmetric variation.

The comments are one move ahead of the actual move. Why is d4 bad? I usually win with that gambit.

Just because you win a game with a particular move doesn't mean that the move itself was a good one.