On the PTR i have noticed that, with the Rushing Streams talent, my Healing Stream Totem will sometimes heal itself - i even confirmed this through the combat log, where it says that HST has healed HST for "some number".
I noticed this issue on my Enha shaman, so i do not know do Elem and Resto's Rushing Streams suffer from the same issue.
I also do not know will the HST try to heal other totems in it's range.
Luckily this issue seems to happen only when there are no wounded people in range of the Healing Stream Totem, but people who use the Glyph of HST (damage reduction) will be displeased to know that HST will be "buffing" itself instead of your teammates when everyone is at full HP.