As you can see, many of my problems came from the opening and White's d-pawn.

Yeah, I agree with the d-pawn becoming too strong--but not necessarily the opening.  White's Bc4 could've been easily refuted by e6; letting him move to d5 was your mistake in the opening. Your opponent also won because he was able to get the e-file and used it to plan an attack.  This was especially important because your king was stuck in the center after your 17th move (open files in the center e or d-files usually lead to a win; just look at the Game of the Century).  Remember: never underestimate castling.  Anyway, hope this helps.