You don't need more light- you need it closer to the plants.. should be within a few inches...
what kind of soil? Are you feeding it?
Looks very dark- almost blue/green with pale center- usually means too much "N"...
don't feed it till she gets her 3rd set of real leaves... but let us know what all you are using so we can help you better...
No need to replant until the plant is as tall/wide as the planter-- you want a well-established root system before youreplant- or you'll slow her down again!
and don't worry hun-- many strains are slow starters- then take off like a shot later on!!