Women who usually have regular menstrual cycles and normal sexual life, if suddenly miss their periods for 2-3 weeks without special reasons, may be pregnant when having the following symptoms: 1. Nausea and vomiting. Around one and a half month after pregnancy, many people will feel nauseous and want to vomit in every morning, or spit saliva from time to time, or even vomit. 2. Picky eater,