Put all four of your bulbs in there. Your plant is the size of a ten day old seedling imho. Gotta get proper light then get nutes figured out. If I was you I would do alot more research so your outcone gets better next time
Is everybody missing the fact that the plants are only getting 7 hours of light? This is whyyour plants are so small. Even for flowering they need 12 hours light 12 dark. For veg state you want alot more light time.
You are flowering some yellowing of bottom leaves is normal. You seem to be doing what most new growers do and freaking out over nothing. How far into flowering are you?