A picture is worth a thousand words.... if you can provide a picture so everyone can see what color they are and what is going on. I am no expert but... there are some here that will help.
need more info on your grow man. As there are tons of variables. What soil are you using? How old are they? What kind of water are you using? Whats the PH Level of the soil? How often do you give nutrients? What kind of lights do you have? and how close? What strain? Bagseed? Whats the temp/humidity like? I'd be glad to help if you could answer these questions or post a pic would be better