Possible chemical ?

Hey y’all so a few days ago I tested two times in two days and got clear faint positives. The second test looked darker but was still faint. So I decided to test again today and both test came out stark negative ( used same urine and I did pee 40 mins before taking the test but I wouldn’t think at this point my pee would be diluted, I could be wrong tho) My period doesn’t come on for another 3 days and I’m still having the same symptoms from which made me test in the first place. Could I be having a chemical? Kinda down so if anyone could help me make sense of this I’d greatly appreciate it.