Std question

So I got tested like a month ago Pap smear and blood test and everything came back normal but a couple of days ago I got some bumps and they checked and said it was genital warts. Could this be a old infection that’s just showing up is that even possible if the tests came back normal. I am pregnant so could it just now be showing up because of my hormones.? My boyfriend swears he hasn’t cheat and I’ve been the only girl he’s been with (I took his virginity). I don’t want to break up with him over nothing. I’m just confused

I’ve only been with him for a year and my ex gave me herpes so maybe it was from him too.? My current bf never has cheated so I hope it’s not from him 😭

Also his sister is a nurse and supposedly she tests him and they both keep telling me that he’s always been clean and never has had a std they both keep saying it wasn’t from him. His brother shares his things sometimes which is gross but he shares like his scrub to clean his body in the shower and sometimes boxers clean boxers but still lol.