Bleeding after 3rd time of having sexual intercourse.

During your puberty, your hymen became thick and elastic. It may not have torn the first time. It may be that as you are getting used to each other, the sex are becoming more vigorous and that caused it to finally tear.

It is also possible that it a micro tear. Most women will have small tears in the vaginal entrance after sex. As you become more experienced, these become less of an issue. If it was rough sex, there may be a tear in the perineum (the soft area at the back of your vagina (between the vagina and the anus). Sometimes his penis will bump into your cervix bruising it and causing light bleeding, If you were dry, friction could have caused small tears. If he hunted for the so called g-spot, he might have scratched you inside.

It may also be some left over menstrual debris, or some breakthrough bleeding pooled inside your uterus that came out when your uterus contracted during your orgasm.

An orgasm can also make your period start a bit earlier, or start again shortly after it finished.

So you can see that the reasons can be varied. Did you take a look with a mirror to see if you can see something? Redness and rawness? Bleeding? A tear? What is the state of your hymen?

If it happens every time, is very heavy or does not stop, you should see your doctor, Else it should just go away after a few times of intercourse.

Take care and remember to stay safe!

The top paragraph sounds about right, thank you so much !