Buying lights questions ... Details included

So I got a normal green bag seed she was growing pretty fast at first but now she's about 1 month old and she have t really grow as much only now that I switch 12/12 more leaves Are alleging now I got 8 pairs of spiki leaves but hey not really growing fast I see. People that are 2 weeks into flowering an their plants tripe in size so since I'm growing onl one plant tomorrow ima buy to more light extensions so ima have 3 light right now I'm using one 120v 50hz cfl so witch light should I buy I'm problay gong to home depo I got a 40$ budget I got everythig I need I got some vigoro fert I got mg soil .. So my questions are what lights should I buy and eat are some stuff I can find to make my plant grow faster heatlyr and stuff rhanksss