I might be pregnant i need advice!?

almost 2 weeks ago i started actually trying with my partner and this past week has been weird, im not late because my period time isnt here yet but im getting weird signs like my lower back get extremely painful around 8pm until i go to bed im getting random cramping but i never get cramps when im not on my period, also it hurts to lay on my stomach and thats my favorite way to lay. Also i have been using the bathroom alot more. i took two at home pregnancy tests one negative and the other had an extremely light positive but my sister is saying its a dud, and i went to planned parenthood and they came back negative i'm extremely confused i know its too early to know yet i should stop worrying till my period come or if i does, i just need advice if these are actual signs of it or not any advice will help!