A few weeks ago my boyfriend masturbated and ejaculated on my stomach. We did not have intercourse and he did not touch my vagina (I was on my period). I was wearing pants so I know none of the semen came into contact with my vagina. Later that day when I was about to take a shower I touched my vagina without washing my hands. Is there any way sperm could have survived on my fingers even after the semen had been dry for at least an hour, and gotten me pregnant? I'm very worried. I'm only 16 and cannot afford to have an accidental pregnancy.