Hey there, welcome to the boards.
So, despite the common thought that first-time vaginal intercourse should hurt, it actually shouldn't, and much of the time, if it does, it's because something isn't right. That something can be:
• the person with the vagina doesn't feel secure or safe or relaxed enough
• the person with the vagina isn't turned on
• lubricant isn't being used
• people are doing sexual things which involve going into the vagina -- with fingers, a penis, whatever -- too soon, or when the person with the vagina actually isn't wanting that at all or very much
• a partner is being too rough, hasty, or just isn't communicating with the person with the vagina to ONLY be doing what feels good
• people are continuing to do things even when it hurts, instead of stopping, or finding ways to do things that feel good instead (pain is a sign to stop, not a sign to keep going)
There's more, but those are some of the most common, and I know you can see some things on there that probably apply to you.
How is this relationship? Can you have honest talks about all this, correct your partner's misinformation, and maybe share some articles together so that you both better understand how to make this go better, and in a way where no one is in pain?
Never doubt that a small group of thoughtful, committed citizens can change the world. Indeed, it is the only thing that ever has. - Margaret Mead