doesn't f's increase from the original F0? so if you have a F0 and a F1 then it would still be the orginal F0's F2 fry. im new to the whole F thing, but it only makes sense that way!
In my understanding, the "F" generation would be based on the farthest from "F0". So, breeding an F1 & F2 would result in an F3. In your case, F0 & F1 will result in F2.