I ended up with a detached head today, the same problem as described in: git push says everything up-to-date even though I have local changes
As far as I know I didn
try
git reflog
this gives you a history of how your HEAD and branch pointers where moved in the past.
e.g. :
88ea06b HEAD@{0}: checkout: moving from DEVELOPMENT to remotes/origin/SomeNiceFeature e47bf80 HEAD@{1}: pull origin DEVELOPMENT: Fast-forward
the top of this list is one reasone one might encounter a DETACHED HEAD state ... checking out a remote tracking branch.