It is possible that your dht lowered and also the sudden increase in estradiol lowered your thyroid function and therefore lowered your shbg.
I’ve personally dropped hcg. I take around 8.5 mg of testosterone daily. Although it is divided between 5.5mg test e and 3mg test p to create a daily spike in testosterone.
I naturally have quite low estradiol and slightly low dht. I’m working on getting my testosterone numbers to in between 700-1000 and estradiol in between 35-50 and dht 70-100.
I think until those are achieved one cannot move to the next thing. Which I would say is thyroid function. To assist with thyroid and adrenal hormone I’d say caffeine in around 200-400mg daily will help. Which is what I’ve chosen to do prior to getting actually medicating with thyroid.