The night after ivf et, fresh transfer, i had strong cramps and ovarian pain for one hour. it is possible to have expelled the two embryos?

Unlikely: What a stressful time and source of worry! I would probably have called my fertility specialist if I were you, but expelling the embryos is unlikely. Many factors are working together to try to get them to implant, and these factors are stronger than you would think. I wouldn't worry about the cramps, etc. Just try to keep calm, breathe deeply, follow your doctor's instructions, and believe!