im 16 and struggled to have a boner during sex /u/ShotRepresentative45 Sex

so we started by kissing for 30m i asked to eat her out but she said no (i watched tutorials on how to eat pussy for 2 hours the day before lmao) then she told me to finger her so i did and i added neck kisses and everything until she did orgasm twice and she liked it a lot then she told me to put it in but i wasnt hard at all i got and erection at the beggining while we kissed for a while then it stopped so we kissed for 30m but i still wasnt hard like at all then she sucked me until i got very hard and i put condom and couldnt put it in in missionary and went soft so she sucked me again and i tried with a new condom to put it in again and i went soft we tried 4x in a row until we tried on cowgirl and she rided me she did enjoy it i could see that and she orgasmed again but i didnt and i actually wasnt even fully hard in her and when i told her to switch positions i instantly went soft again so we stopped (i didnt cum during the session) my problem is i really struggled to get hard btw im in good health i lift weight good shape good diet hydrated but i masturbate almost everyday or once in two days i find her attractive yes i was nervous but not that much i dont really think thats the issue but i wanna know guys if you have any advice for me to not lose my hard again that easy or something i could do that will help me get a boner easier (i forgot to mention but this is my first time and her 4th time)

so we started by kissing for 30m i asked to eat her out but she said no (i watched tutorials on how to eat pussy for 2 hours the day before lmao) then she told me to finger her so i did and i added neck kisses and everything until she did orgasm twice and she liked it a lot then she told me to put it in but i wasnt hard at all i got and erection at the beggining while we kissed for a while then it stopped so we kissed for 30m but i still wasnt hard like at all then she sucked me until i got very hard and i put condom and couldnt put it in in missionary and went soft so she sucked me again and i tried with a new condom to put it in again and i went soft we tried 4x in a row until we tried on cowgirl and she rided me she did enjoy it i could see that and she orgasmed again but i didnt and i actually wasnt even fully hard in her and when i told her to switch positions i instantly went soft again so we stopped (i didnt cum during the session) my problem is i really struggled to get hard btw im in good health i lift weight good shape good diet hydrated but i masturbate almost everyday or once in two days i find her attractive yes i was nervous but not that much i dont really think thats the issue but i wanna know guys if you have any advice for me to not lose my hard again that easy or something i could do that will help me get a boner easier (i forgot to mention but this is my first time and her 4th time)