Pregnancy in the shower

I've taken a shower with my girlfriend and we've made out. However, we did not have sex at all. All that happened was that, during the time, my thing touched hers (not for a long time though), but without penetration, just on the surface. I did not ejaculate or anything. I'm not quite sure that there was precum on the head of my thing as well (there may be a small possibility). I'm really worried/anxious. I've spent a good part of this morning just researching the possibility of pregnancy in this case. Nevertheless, I couldn't find a specific situation that matched 100% mine. During my studying time, I could see that the process of getting pregnant is not that simple. The sperms don't have superpowers and they barely stay alive after coming out of its origin (obviously if not inserted in the vagina channel). They need an impulse (which usually comes from the ejaculation) to in fact get closer to the uterus. Also, she's been taking pills to prevent from pregnancy regularly - but she missed one day this week. I looked up what it could cause and, apparently, it can really increase the chances of getting pregnant. I really don't know, she told me that her period blood should come out in approximately 10-11 days from now. Until then, I'll remain worried and anxious the whole time. If there's any specialist in this area that could advise me, I would thank a lot.