For the branches growing close to one another (I'm assuming I read that right - one branch touching the other?), just pull it out of the way! The plant will grow how it wants so it can get the best light it can. If that means some overlap, not a huge deal. You also can use sticks/stakes to tie the branches LIGHTLY to so as they are in the places you want them to be in. Occasionally plants grow wonky and will do something like this, but you can train it to grow how you like.

As for the leaf? It may be just that it's not getting enough light. Possible, but hard to tell. I don't know cannabis too well yet, and i normally grow plants outside and don't worry other than water, bugs, and fungal growths... It may be shedding that leaf to concentrate growth elsewhere, too.