Defiantly harvesting too early, You want to harvest when the trichomes turn to an amber color. Now you need a magnifying glass to check this. Another factor is when the hairs on the plant change color also. When about 75% of the hairs turn red or brown, and the trichomes turn amber then you want to harvest. This meens that the plant is at its peak point in the developement of the canaboids and thc (which is the good stuff). If you harvest too late you lose some THC, so id recommend doing it the way i just explained to you buddy.
fyi, there is such a thing as diminishing returns, which is when the bud starts to not produce stuff that is beneficial, or takes away from the high, im not a expert, but i think thats fairly close to the explanation