I think what happened is severe sunburn, especially if your branch is firm. The soil line is down too low and that exposed area of the pot just cooks the branches.

You can leave that branch and see if it continues to grow, sometimes they keep on growing. Or you can trim the branch off and make a cutting out of it and root that.

Either way my advice is to raise that soil level as soon as possible to avoid even more damage. Hope this helps.