I m female 25, TTC. My periods is late by 10 days. Im regular with a 30-32 day cycle. And I have pregnancy symptoms like nausea,fatigue, headache, constipation, food cravings & smell aversions..I took 2 home pregnancy tests.. Both were negative.. Today I went to the doctor. She again took a urine test and it was negative too. She has prescribed Regestrone 5 mg tablets for 3 days. Is it safe to use ?. May I still be pregnant ?. What is happening in my system ?. How should I proceed ?.