SEX HELPPPP

ok so my SO and i had sex for the first time today and everything was going well.He put a condom on and we were being sad once he puts it in it just didn’t feel right like i couldn’t feel any thing and neither could he like at some parts it felt soo good but others i could barely feel it and like me tell you he is very very large so i was so confused and so was he maybe it was the condoms maybe it was the position idk i need help pleasee