Hello Thanks for your query. If you had unprotected sex, specially during ovulatory days, then chances of pregnancy are definitely there. As a method of contraception, withdrawal method is one of the least effective, as pre ejaculatory fluid also contains active sperms. You need to wait till you miss your period, and then test using the pregnancy urine HCG kit to confirm your pregnancy. THe vomiting could be due to early pregnancy, or other causes like mild gastroenteritis etc. No way to know unless you perform the pregnancy test. Random nosebleeds are not common in pregnancy, and you should check your blood pressure, as well as rule out habitual nosepicking. A proper ENT ( ear nose throat ) consultation is in order. Take care.