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The rupture of hymen and loss of virginity can only be confirmed after careful examination done by a gynecologist. The spot/dot of blood that you saw could be due to possibility of internal injury. The bleeding from hymen rupture usually lasts a few hours and is mild. Consider visiting your doctor/gynecologist for further assistance. If you intend to remain sexually active, consider visiting your gynecologist to get started on suitable regular birth control measures to be protected (after your periods). Be regular with birth control use as instructed. Avoid having unprotected sexual contact.
If there was semen or pre-cum that came in contact with vagina, then consider taking emergency contraceptive within 48 hours of the unprotected sexual contact to prevent pregnancy.
Take care.