Yes, you can get pregnant. You can not wipe the 'danger' away. Sperm goes up inside your cervix and ejaculate (or leftover semen) flows back out which is what you wiped away. Get Plan B (or another emergency contraceptive) urgently!!!!
The good news (if there is any) is that you are not guaranteed to get pregnant. Only about one third of the women that have sex at this time will get pregnant.
Please use condoms in future to prevent you from getting pregnant and to protect you from STDs.