How long ago was this incident you speak of? My wart came pretty fast which was just under a month. But genital warts can appear Within 3 months or more of exposure or even longer. If you're just a couple of days after your encounter, then it's probably not a wart. However, when in doubt, always go see a medical professional. A doctor or a dermatologist will be able to tell you.
Go to Planned Parenthood or see your GYN for an exam. Do not remove it yourself. If warranted, ask the doctor to get it biopsied for HPV.
Did you find out what it was