While you are correct, there are some tests out there that pick up nandrolone as test. I learned all about it the hard way. I was checking it myself and showing perfect levels, but then a week later my TRT doc would draw blood and show >1500. If you google ECLIA and nandrolone you can find the FDA acceptance report that documents this shortcoming in the ECLIA test. I ended up pissing that doc off bad enough I had to find a new one. Was an expensive lesson.
It sounds like OP is squared away now but I though I would add that for the benefit of anyone else reading that's on TRT.
I've been saying this on forums for years yet people continue to disagree with me and flame me
all AAS are derived from testosterone and on certain tests you damn well better believe they can show up. also you are correct, tren can show up as a false positive for E as well.
like I said a smart doctor will be able to easily figure out you are taking AAS, but most of them are too dumb to understand what they are seeing