If I may:
The OP swallowed 1/3 of a 12.5ug/hour patch (MICROgrams per hour). The total amount of Fentanyl contained in a 12.5ug/hour patch is around 2.1mg (MILLIgrams) assuming it was a Durogresic Dtrans patch (other brands may contain slightly more or slightly less of course). And this is the equivalent of 210mg of Morphine.
The oral bioavailability of Fentanyl is anywhere between 33% and 50% (depends on how lucky, or unlucky, you are i.e. depends from what point of view you're looking at all of this! Lol!).
The LD50 of Fentanyl is 2mg (seems to be the generally accepted standard worldwide).
Way I see it:
The OP ingested 0.7mg of Fentanyl and of that a maximum of 50% was absorbed = 0.35mg of "fun Fentanyl" (give or take) (and which bear in mind would still not all be released at once from the patch although it would indeed be released faster than transdermally).
"Expert" Opinion
:
Best case scenario: the OP got the absolute mildest of a buzz. Worst case scenario: the OP choked on the patch.
As with any "paper" of this kind certain assumptions are made and are to be disclosed:
The OP was not using any other medications, in particular Benzodiazapenes, at the time.
The OP had only applied, and had only been applying at any given time, one 12.5ug/hour patch (which was removed during the panic).
The OP weighed more than 1kg.
"Expert: Conclusion
:
While it's NOT IMPOSSIBLE it is HIGHLY UNLIKELY, given all of the above based on the limited amount of information made available by the OP, that the OP died of a Fentanyl overdose.