Chiming in with the choir, estrogen for me (sublingual tabs) took a good month to feel, erections persisted for a number of months at least, semen did not change regarding amount, clarity, etc for a number of months, breast tenderness was quickest, and even that was about a month. And that's with anti-androgens for a few months prior to starting E. Not saying it isn't possible, but the effect (as pleasant as it might be, and as valid for the poster) is almost certainly psychosomatic. But keep going, and kudos on finding a partner loving enough for this journey. They're pretty rare, so treat her well! Good luck!