One thing you can do is remove the quiver and shoot the bow.See if this helps make it more quiet. Quivers are notorious noise makers. Going to carbon arrows (lighter) will net more speed, but then the noise level goes up. Something to consider.
It could be that the bow isn't tuned well and the arrows are hitting the rest or riser. Getting the cams timed well can alleviate some noise as can tuning the bow/arrow combination.
You can install Limb Savers and a decent stabilizer (Simms S-Coil won't break the bank). Maybe install a set of Cat Whiskers on the cables. These won't adversely affect the speed. Any or all of these things will help absorb bow vibration and reduce noise somewhat.
I wouldn't be so quick to buy new arrows (carbon) till you address the noise issue and get it within acceptable limits.
And in the future don't bleat at a deer that is almost motionless. All you accomplish is alerting the deer to something foreign. Keep 'em relaxed and just make a good shot.
And for what it's worth congrats on your deer and I applaud your concern to become a better hunter.