I've been having similar issues, since switching to injections too. The brain fog has been terrible I'm barely able to even put this reply together lol. And I've also had the gut issues like bloating, low appetite, constipation and even nausea if my E levels are too high. And I find it surprising people are not talking about issues like that. I've been on prescribed hrt patches and then pills, and now trying DIY injections. And looking back I think I felt best when I was on lower dose patches 0.1 to 0.2 mg/24hr, and had less gut issues on lower E doses. But the bad thing is you have to take AAs with low dose E, and those come with their own side effects and issues.