This year is my first time attempting a medical grow. I'm about two months into it. One month of vegetative growth and a month into flowering. I feel as though I have learned a solid amount from lurking Rollitup and several other forums/ resourcrs. Of nine plants two of them are looking similar to yours. I am giving them slightly more light than the others and only watering twice a week and they are still not thriving. Tempted to mark this one up to bad luck, but if you find a solution I am definitely interested.
I know Nitrogen facilitates growth during veg. so perhaps that would help.