It's ok to harvest, or stunted? will be better?

Hard to tell from pics and I don't know your setup so take this info with a grain of salt. It's pretty typical for heavy sativas to go 16 sometimes 16+ weeks of flowering. That being said, 24k Gold (DNA) isn't a long flowering sativa. The buds on your plant look pretty immature. 1. Are your top buds just as immature as the bottom? If its only your bottom buds, you may not have enough light reaching them. 2. What does your light cycle look like? Do you have light leaks? Using a 11/13 light cycle instead of a 12/12 can sometimes help your plant finish faster. Light leaks during lights off can sometimes make your plant re-veg, stopping bud production. 3. Unlikely it is a nutrient issue, as your plant looks like its fading normally. I don't notice any serious leaf issues. Good luck and I hope your plant finishes up!