Period was 2m late so i got it 2d ago but its only spotting w/stomach cramps lower back pain and nausea. what could it be? it just feels weird

Irregular periods: Irregular periods are one of the most common problems Obgyns treat. If this is one time problem it usually resolves on its own. If this is a recurring problem you should be evaluated. Infections & hormonal changes can cause spotting. If there is a concern for pregnancy then do a home pregnancy test . There are many options available to help regulate the menstrual cycle. Schedule a visit.