Hallow Dear, Your history is suggestive of possibility of pregnancy. Let me explain the events you have described. The spotting with pain in abdomen you had in the mid January period is most likely what is called as Mittelschmerz. It the a phenomenon of bleeding with abdominal pain at the time of egg release. Since you had intercourse on that day, the chances of pregnancy are very high. Now you have missed period, moreover you have nausea, tenderness of the breasts with some secretions from the nipples. This is all suggestive of pregnancy. Still if you have any doubt or want a proof of documentation, you may go for urine pregnancy test a week after the missed period. This test gives best results if performed on the overnight morning first urine sample. I hope this helps you. DR. Nishikant Shrotri