So tonight was my second night of using the gonal-f pen and for some reason it wouldn’t discharge the full dose of 150, there was 25 left. I changed the tip and tried injecting the remaining 25 but it just stayed on the screen. I called the nurse and she said to just use 25 from another pen for now, which worked fine. I didn’t have this problem yesterday - the same pen worked fine. Is it maybe something I’m doing wrong? Has anyone else experienced this?