If your work was "described in a printed publication, or in public use, on sale, or otherwise available to the public" before the patent's priority data, it is available as prior art.[1] That doesn't mean you're immune, per se, but it does mean that nobody can patent
exactly what you had made available.
[1] http://uscode.house.gov/view.xhtml?req=granuleid:USC-prelim-...