possible chemical?

i got three EXTREMELY faint positives last week. like I’m talkin, they were barely there. two were frer and one was a Walmart cheapie. others were able to see the line though so i kept testing. the line never got darker and I’m back to stark negative. this was last Tuesday, Wednesday and Thursday that i got these tests. This morning i woke up to the start of my period. does this sound like a chemical? or were they just false positives? this has been a whirlwind week of emotions and I’m just not sure how to feel right now. and advice is appreciated.