I've had my period for 1 month and 1 week, 4 days ago i started to expel blood clots small size, never my period had lasted so long.

Pregnant?: Pregnancy is always a possibility. Purchase and perform a home pregnancy test. They usually become positive when you're about a week late. If it's negative, repeat it in 1 week and see your doctor.

Likely hormonal but.: The single most likely cause is hormone change which is not serious....But there are many other possible causes. A more complete history and a n examination are needed to better understand the exact cause.