D.B.
It doesn't make sense to take 7 home tests (if that's what you mean) - you have lasting symptoms that indicate a problem (back pains/ stomach pains, although I'm not sure what the cold has to do with it). So you do what any smart person would do - you contact your doctor for a more accurate pregnancy blood test (and maybe additional blood work), a pelvic exam, and a review of your other complaints and possible causes. There's a limit to the internet and a time to consult a qualified medical professional.