This OTC stuff won't do anything for gyno. Unfortunately pubertal gyno (assuming given your age) is less responsive to pharmaceutical treatments. I do know that Letrozole can be used to get rid of or considerably shrink existing gyno, though it's more responsive in AAS-induced gyno.
I have pubertal gyno myself (not very bad though, but yeah it is annoying) and have use Letro. While it doesn't completely shrink it away it does a considerably good job at making it less noticeable. Search for the letrozole gyno protocol. Anthony Roberts posted it a while back.
I'd also suggest doing a very thorough taper off of any anti-E and AI meds that you use, as you can experience delayed gyno from the estrogen backlash if you abruptly stop treatment. Also understand that since you already have gyno, using any AAS could potentially set you up for worse gyno symptoms than the average user.