like piggy said, just pick off the part of the leaf with the white on it. my leaves have had white powder on them, but thats from the dolomite lime i think..not sure if u used that at all. as far as bugs, Ive heard the tobacco juice is a great method to kill/prevent them. Your plant still has another month at least in my opinion..at the very earliest 21 days or so. As far as the shortness, yes, her being an autoflower and planted outside so early in the season def couldve played a factor in her height. Not sure where you live or what the weather is like, but if it gets too hot or too cold, it will def suspend growth or stunt her.