I'm sure that I am just worrying about nothing, but this has never happened to me before. My period is pretty irregular, with my cycle being anywhere from 30 to 40 (or sometimes more) days. My last period was April 21, and since then I have been under a fair amount of stress- I had final exams and I flew on an airplane for the first time and by myself, along with some other things. So, it wouldn't surprise me if I just missed my period all together this month. However, I had very light, brown spotting on May 20 that lasted not even a day, and I only noticed it on the toilet paper after I used the bathroom. I've never spotted before, and when I looked it up online, it said that this happens during implantation. I've had protected sex a couple of times since my last period, but the condom always remained intact and did not slip off. I'm not completely ruling out pregnancy, but I find it very unlikely. Has this happened to anyone else, or does anyone know what could be causing this? Thanks!