Sex for more than one hour

Hi. I have hot in a relationship with a guy and we started having sex a couple days ago.
Yesterday, we had sex three times. The first time took less than 20 minutes and it was good. The second one took more than 45 minutes and it was really painful for me. The third one was more than an hour and was so painful for me that I couldn't continue and ask him to stop. He didn't *****.
I like this guy but this stuff made me a little worry about our future sex life. I want to get an appointment with a doctor to find out why sex is so painful for me.
I also had only 17 sex in my whole life and it started several months ago.
How do I feel more comfortable with having sex with this guy?
How would he feel if I discuss this more with him and ask him we have less sex?

Perhaps it was too dry and needed more lubrication so use oil or lube next time. Anyway that sure is very long time to last. If you engage him before he enters you, like oral and such then he should end sooner.

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Lube.....lots and lots of lube. There are other ways to have sex other than vaginal. Who cares if you take a break to heal.....don't burn yourself out.

It doesn't all have to be penetration. Spend time kissing, touching, massaging, etc. being slammed for an hour straight isn't sexy or pleasurable.

A normal sexy procedure always takes 15-30 mins and will be a proper time for physical strength and sexual pleasure. Dont make it too long and it hurts your body if the penetration is too long. As the above sayings, oil and lube can be helpful in the penetration part bt if there is condom it may not be so workable.

is he a 'big' guy? I know if i'm with my gf for too long she gets sore and worn out also. but she is plenty lubed up. just not used to me.

Omg, 1 hour, continuous? Way too long.