Can u trust blue dye pregnancy tests

I've been told they give alot of false readings. And I've missed yesturday and today( it about to be the next morning). I've not been stressed and last month my period was late 4 days then lightly bleed for two days with a weird coloring. And the test I took a week ago someone told me to not buy them but I had two pregnancy tests with it so I just took it and again negative but the control line felt like it took forever to pop up like the last test which was almost immediately and then it does for the purple/ red dye cause I took that test with my son. Any advice i dont want to waste money but I've been having alot of the pregnancy symptoms! If u have any questions just comment I'll answer rt away!