Yes you can release two eggs at one ovulation (twins) or three (triplets) and so on. Don't know if you can harvest one for implantation, you would have to plan the harvesting rather precisely.
What you are describing during menstruation is not a sign of pregnancy. Menstruating is different with all women.
What you are describing during menstruation is not a sign of pregnancy. Menstruating is different with all women.