so, how is Loki... (spoilers ahead)
...still alive, and where is Odin?
In regards to Loki, it wasn't a fatal wound - he only pretended it was to (once again) fake his death and worm his way into getting what he wants.
As for where is Odin? The next Thor movie, Thor: Ragnarok (coming out next year), will answer that.
Nillindeiel
Agent Hill: ...Then aliens invaded New York and were beaten back, by among others, a giant green monster, a costumed hero from the 40's.... and a god.
Agent Ward: I don't think Thor is technically a god.
Hill: Well...you haven't been near his arms.
~Agents of SHIELD; Season 1 Episode 1 "Pilot"