Worried really worried

So I have taken three pregnancy test and they all say yes I'm pregnant but they were really cheap ones and I think they were old too so I'm doubtful. Only because I feel like I'm about to start my period I'm cramping my breasts are tender and it just feels like I'm about to start. So I don't know what to do buy a more expensive pregnancy test or try to wait it out for my period to maybe start. I'm just really confused and scared.