1) worst case physical pain: like being cut by a knife and bloody.
Best case... let's not talk about best case.
2) worst case emotional pain: he left and block you the next day.
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Now the how to:
3) use missionary position, perhaps with your legs on his shoulders.
Talk beforehand, when he finally penetrates, do it with a quick, hard thrust.
4) "finally" of point 3 means lots of foreplay.
Principle: he makes you very wet and horny, so much so that you CRAVE him inside.
A) after you enter the bedroom, and start to undress, use the bathroom together. It helps in hygiene and removes a lot of awkwardness when you two washes each other.
B) do not off the lights, do not dress up of cover yourself again. Instead have the mind set to show each other everything. Yes, everything, including your butt hole.
C) relax. And request him to learn to learn and sensually massage you.
D) relax. Try fingering.
E) relax. Try oral.
F) relax and become wet. It's OK to cum also.
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Eventually you'll want him inside. Then tell him to do it.
It doesn't exactly work that way. Regardless of a man's size, be it 3 inches, or 12 inches; he can only go as far as is physically possible.
As you can see in the diagram, your vagina and uterus are separated by your cervix. That is essentially the end of your vagina, and as far as he will be able to go. It will not reach past your belly button.
Now, as for whether it will hurt or not, will depend on a number of factors. How relaxed you are, at the time, how gentle he is, and the amount of lubrication, whether that includes your natural wetness, or some form of store bought lube. If you're tense, too dry, or he just rams it in, then it's going to hurt.
It's also possible that it may hurt if and when he reaches your cervix. I'm obviously not female, so I can't speak for them, but it is my understanding that many women find that uncomfortable, while some claim to enjoy it. Again, though, if he just starts hammering it, it likely won't feel too great.
The most important thing the two of you can is communicate with each other. If something doesn't feel good, don't be afraid to tell him. It shouldn't hurt, but a lack of communication can lead to pain that otherwise could have been avoided, simply by telling him.
Your friends are immature as hell. Penises do not work that way. Having a big member has nothing to do with height. Step one is you should be keeping your sex life private because the only ones that made you scared is your friends with their immature remarks.
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I'm not sure if this is allowed on here, but the next pic might give some clarification. It's made with an MRI, e. g. a device that can see inside your living body, much like an x-ray but without the risks for radiation. They once asked some couples to have sex in such a thing to see how things look from the inside.
I assume you recognise most parts, also where your belly button would be, and during arousal your internal parts can become bigger to accommodate for length.
Use the cowgirl position. This way, you can control how deeply he penetrates you and also your own pleasure and pain. Being this is your first time, you should have as much control as possible and, with cowgirl, you do.
It shouldn't hurt. You'll be fine. If you do end up having issues, though, use lubricant. On the off chance that doesn't work, there are toys you can use to help you stretch more.
Move on
IT HURTS VERY BAD
It won't hurt. Just relax.
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