For the past few days I have had my period. I've been getting sick though and mood swings. What could this mean?

Symptoms during. period. Changes in hormones are likely a causative agent for feeling off and moodiness during your period.
Menses. Depends on how old you are. Could you possibly be pregnant? Is this cycle irregular? If so you can speak with your gyn or primary care to do testing to look into regulating your cycle.