Morning KG1.
Suffocation (as opposed to strangulation) can be subtle to define, especially after 10 days, but would be fairly obvious on the autopsy table. Yes, petechiae would be likely. Strangulation (i.e. manual neck compression) would leave bruising, and depending on the force of compression, fracture of the hyoid bone in the front of the neck is common, although not 100% present.
Neither would explain the chipped tooth (it's hard to chip your own tooth - more likely to have bitten her own tongue or inside of cheek or lip), yet a blow could chip a tooth, as also could biting down on something hard, eg something being forced into the mouth - like the neck of a bottle, for example.
As for moving the body - there are several ways to tell if the body has been moved post mortem, including the position of what is known as lividity. That is where the blood, which is now basically static, settles towards the bottom of the body when in the resting position. This only takes a few hours to occur (between 30 minutes and 3 or 4 hours), and leaves telltale "staining" and discolouration. if the body had been moved after lividity occurred, either by the perpetrator or by a fast-flowing creek, it would be highly unlikely that the body would end up in exactly the same position as it was before.
You may find this link useful, although somewhat technical:
http://www.somerset.k12.md.us/JMT/postmortem_changes.htm
As gruesome as it is, I hope that all makes sense.....