Interesting question - I did on the very first three day cycle, horrendous shakiness, feeling spaced out, panicky and heart palpitations. I took it on the third day and obviously it subsided but it hasn’t happened since. Maybe my body has got used to expecting a progesterone boost every 3 days, who knows? I just hope I can continue like this as I’m tired of this minefield called HRT! There are other options for progesterone - mirena, although synthetic, apparently gives off a very low dose so might have fewer side effects (women report variable experiences). Worse case scenario is for me to go back to Evorel conti which, although I felt quite settled with it, I want to stick with body identical hormones as far as possible.