You had first intercourse with your partner and have slight bleeding with intervals.
It is called Post Coital Bleeding probably due to rupture of your hymen
which is quite common and natural thing,occurs mostly in female with fist sex.
Bleeding will stop automatically after healing the rupture site.
So don't be much worried. Avoid sex for 2-3 days. For pain,you may take some analgesics. Maintain your hygiene to avoid infection.
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