Bleeding in first time sexual intercourse is quite common & it is due to rupture of hymen. Usually bleeding is mild and stopped automatically in 2-3 days when it is healed up.Pregnancy
is possible only if unprotected sex is done with ejaculation around ovulation time or fertile days in regular cycle. So you can be pregnant from first time sex.
Here, you need to undergo one blood test
for beta hCG
and TVS scan to rule out product of conception if any as it may correspond with implantation
bleeding or early sign of miscarriage
Following test reports, you can contact with gynecologist for next line of management. Maintain your personal hygiene properly.
Always practice safe sex in future to avoid unwanted pregnancy & unnecessary vaginal bleeding. Be well & take care.