Um, you are only starting to flower, a process that can take 6-16 weeks.
Never compare your grow directly with other peoples grows, the list of variables affecting the outcomes is huge. Things like light type and intensity, temps, growing methods, nutrition, grower experience, root room, and the biggest factor of all, the individual genetics contained in the seed you planted.
Be patient, all will be fine, just remember not to defoliate, your plant needs every leaf it has to produce the energy it needs for its biggest and fastest growth.
Hope this helps,............
Organoman.