I have a few questions in this game.
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5.c3 is fine (I personally play nc3), although 4.bc4 isnt best, black should have played 4.d5
14.g4 isnt good but its not bad enough to be considered a blunder. Perhaps better is f4 to secure your hanging pawn.
Check this out http://en.lichess.org/6bsBk4cM#27 it did wonders for me, hopefully itll help you.