I also have low SHBG. Last labs had mine at 12 (on a scale of 10-50). I've only been on TRT for a little over a year, but have experimented with various protocols already. For a long time I was only daily injections at 20 mg a day, but I've recently switched to injecting 60 mg every 3.5 days for a total of 120 mg a week. I know most people say "if you have low SHBG then more frequent injections will be good for you", but I started to wonder if always having my levels high and never giving them a chance to fall a bit and give my body a break was a good thing. That's why I'm trying every 3.5 days for a while now. I can say when I first made the switch, by the time injection day came, I was feeling it. Felt tired, just blah. But, at the same time, it also felt good for some reason. Almost like collapsing in the recliner at the end of an exhausting day, knowing that my body was enjoying the rest. As for an AI, I also go back and forth because having low SHBG, I'm sure my free E2 is usually high. When I take an AI, I feel better in some ways, worse in others. The same is true for when I stop using an AI. I think that's why I go back and forth, just to change it up as far as what crappy side effects I am feeling so it doesn't get old. Even with the difficulty I've had in getting things dialed in, if I think back to how I felt before TRT, I'd still choose this complicated life of constantly trying to get the perfect protocol. My goal has definitely been to be 100% off the AIs, but I haven't been able to accomplish that yet.
Sounds familiar to me, for sure. I once went two weeks without an AI, but I restarted because I started to get emotional.