whats wrong with my plant??

what should i do, what do i need to buy, how can i save my plants, they are in flowering stage. pics attached

its natural to have a few yellowing leaves just hope it don't get worse. your leaves are very dark green watch you don't overfeed them and get nute burn. otherwise looking good.

Is there white powdery stuff on that plant? It looks like there is in that picture... are u sure it doesnt have mold?

i think its just the camera cause theres no white powdery stuff on the plant