HI dude!
Are you sure your pot is 15l in size? To me it looks like you might want to transplant her in to a bigger pot! Has the side branches grown bigger in size in these last days? Maybe your girl is just bushier pheno and shes stretching sideways now. Nothing wrong with that and its totally normal just be sure shes growing, don't have to be growing in height to be healthy! π
Train her lst get your self some tent pegs and Bush her out more she seems perfectly happy gud luck mate don't expect to much from 1st grow its only about leaning your 1st grow
Raise your light up a bit maybe 6-10 inches depending where you have it this will cause the plant to reach and stretch for the light! Also keep in mind once she starts to flower she will double in size ! She is very healthy so raising the light a bit should give you the results your after! π― good luck ππ