Sex help? it’s not working?

hi, i’m 17 and my boyfriend is 18 ( don’t judge because we’re kinda young) we’ve been together for over a year and a half now and have recently tried having sex for the first time. warning there might be some TMI coming up. we tried in january before he went back to school and it was pretty painful so we stopped and just thought we didn’t do enough fore-play. then the past weekend i was visiting him at college and we tried 2 times and both times it wasn’t very good. both times we did a lot of fore-play (about an hour or so) and i was very wet and he was very hard. the first time after trying multiple positions, he got in and was thrusting (i was on his lap) and all of a sudden i got really lightheaded and thought i was gonna faint so we stopped and just fell asleep after cuddling. the second time we tried the same position because it worked last time and it began to hurt shortly after. i don’t know what we’re doing wrong, we both really love each other and trust each other, and we both want to have sex with each other, we just can’t get it to work. neither of us finished anytime we had sex and we’re both getting kinda frustrated because we want to have sex with each other to add that new level of intimacy to our relationship and we’re struggling a lot. is this normal? is there any advice?

we use trojan condoms and add some lube with them but not a lot because we both have sensitive skin.

we’re thinking of trying to add more lube?

thank you so much for any help or advice you have.