Take a deep breath, relax
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Guys that flare up with gyno usually panic like this. I did
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The studies on high estrogen is usually more on the long term. You won't get any crazy symptoms overnight so relax first of all.
Arimidex or Aromasin or Letrozole work in different ways but produce pretty much the same results at different doses. Don't blame the L-stane as being bad because you didn't use enough. If you feel that you want to switch you can do so to Arimidex @ 0.5mg EOD, I would do 0.5mg ED for the next couple days to try to drop the estrogen a little quicker and then keep doing 0.5mg EOD.
Edit: Or a week like austinite says! Just try to get a good understanding of how your estrogen is getting balanced. Doing a caliper test to measure your BF is a good indicator for me. Normally I cruise around 9-10%BF if I bloat a lot I get a couple percent higher. When I am low on estrogen bordering to extremely low my BF reading will be 6%.