Need Help With a Sickly Stem

Ok! first post in quite some time here, im very worried about my plant i was given this clone to make a mother plant out of so its important i can save her, or ill have to start from scratch again

i was told the strain is romulan , its very nice n bushy for how small it is, but down towards the bottom part of the stem there is a weak looking part that has turned white, take a look at the pics, my plan was to just trim the plant at the bottom and try to burry the plant a bit more :S

heres a couple more pics, hard to get good ones with cell phone

It looks like it has been attacked by something, a dog maybe?

Also it looks like it just needs time to establish itself without any more interuptions. That means no trimming or shaping or anything of the sort. It looks to me like the roots have not 'spread out' in the tub. Best thing would be to let it just be alone for a week or so, letting the pot dry right out before watering it again. Plants like that dry period, and too much water in the pot suffocates plant root systems.

its been like that for over a week hasnt got any worse or better but that is that main stem and it is a little flimsy if i put a fan too near