Little nervous

Hey guys so I had sex for the first time June 16th he pulled out and everything I took a plan b afterwards. I did get my period afterwards. I took a pregnancy test July 10th and it was negative and I also took another just to be safe on July 20th ... I think I’m nervous because the plan b started to dissolve a bit before I could take it . I have been feeling like little spams in my stomach and legs and stuff and idk I was feeling stuff and a I pee more often . But that could be because I do have a uti and I’m waiting for my antibiotics to come . & I’m just nervous because my friend said pregnancy tests are always wrong so I’m freaking out