I Have Been Experiencing Dull Pain In My Lower Left

i have been experiencing dull pain in my lower left abdomen for the past 10 days. The only other symptom is nausea. Any ideas? I am hoping it is a pulled ab muscle as I practice pilates every day. Am wondering if it might be something to do with ovaries. Last period was normal and no unusual cramping. it feels like the mild cramping just stuck around .