confused

So I've been having unprotected sex daily with my boyfriend for over a month and according to this app my period is 4 days late.. well actually I completely missed it it says my period was supposed to be from the 18-21 and I haven't had it at all or any signs of it coming. I took 2 blue dye tests and got very faint positive lines but heard they could be false positives.. I don't know whether I could be pregnant or missed my period completely because of stress i need advice on what to do