Swollen lymph nodes under jaw (2cm), no other symptoms, late period (2weeks late), mood wings. lymph nodes are soft, movable and painless. normal?

Many reasons: L lymph nodes can be a large because they may drain infection, they may be more of a systemic inflammatory , if they were one side suggested may well be a local area. Your physician should be able to help clarify why they're swollen. I am uncertain if there's any relationship to your cycle

Period 2 weeks late can signify pregnancy. If so, hormone swings are not unusual. Swollen nodes under jaw, however, especially if one sided, indicates infection (tooth, gums) on that side of the lower jaw. If home pregnancy test is positive, immediately schedule with an OBGyn. As to infection (which can harm baby) see Dentist ASAP.