as a relatively new researcher, I have little to no idea on lab protocol. I should discuss things with my professor before they become an issue. case in point, yesterday I woke up with a moderate case of the 24-hour flu. there was no way I could sit and plug away at code. so, a full two hours before I was expected in the lab, I emailed my professor a short but effective statement, since I didn't have a number to call, and assured myself that she would reply with a "that's fine, just look over some papers and be in tomorrow." I fell asleep for most of the day, and received no reply. 11 am, 3 pm, 7 pm, 10 pm, and no email. I started to worry. I broke expectations. I wasn't allowed to take sick days. I stressed like only a physicist knows how to. today, I was on time to the lab, greeted my coworker nervously, sure that he would demand where I had been. turns out, my professor apparently didn't notice I hadn't been there. I'm going to discuss my vacation with her now.