My daughter just had 3 negative LFTs over 3 days, immediately followed by a positive PCR. It is well known they are not reliable, hence why you shouldn't actually do them if you have symptoms. I did the LFTs because I knew she was exposed to covid, then as soon as she developed symptoms, I got her a PCR. That was a few hours after the last negative LFT. Good luck OP, the rest of us are awaiting results too.