Pain in lower left abdomen, 8 weeks pregnant (Part 2)

I wrote yesterday about a pain I am experiencing in the lower left abdomen. It became unbearable and have radiated to my left leg. I decided to get checked at KKH O&G Emergency Clinic this morning. They did a thorough Ultrasound Scan, confirmed baby is OK. But unable to find any reason for the pain. I was given two options: 1) admission for observation and investigation - possibly with CT scan, which has risk to baby or 2) discharge with panadol and own observation. I really don't know what I should do now. Anyone experience this before? Please share your experience?