Positive frer this morning but negative at doctor

I tested this morning with a frer test and it was pretty positive. But fast forward to now, the doctor at the walk-in clinic said they did two tests that both came back negative so now they are going to run a blood test which the results won’t be available for 1-2 days and I just can’t wait that long! I don’t know what to think :( Has this happened to anyone else?