The last person who answered this made the answer long and immature, but yes, a creampie can get you pregnant as the female reproductive organs only need 1 sperm cell to survive entry into the fallopian tube.
It all depends on whether or not the woman is on contraceptives or on the "morning after" pill. If she is than yes its still possible but not as likely, if no than the answer would be yes, unless she...
No. Since you can only get pregnant during ovulation, and since you do not ovulate while you are pregnant, then no, you cannot get pregnant again until after giving birth. Provided you only have one...