progesterone induced gyno is an absolute bitch! if you are on fina and are pretty sure it is the cause of the gyno, stop the fina immediately! the good thing is that it is a fast acting drug and will clear your system in about three days. probably will clear up.
anti aromitising drugs like arimidex, as well as estrogen blockers like nolva will do little to nothing to combat the problem if it is progesterone induced. you need to block the progesterone receptors and the only known progesterone blocker is "the day after" female abortion pill. good luck finding any or getting a doctor to prescribe it.
i got gyno from deca. totally fucked me. unlike fina, deca is long acting and dosen't drop to trivial levels for over three weeks, so a single injection of deca, if sensitive is enough to cause a pretty good case of gyno.
a good way to tell if your gyno is progesterone induced is the symptoms. with progesterone there is no "hard painful lump" benind the nipple. only puffy, wattery sensitive nipples.
fina alone is pretty safe with regards to gyno. the progesterone needs estrogen to activate it. unless you are using an aromitising steroid with the fina, you should be ok.
good luck bro!!