No positives but late period?

Hi-

All month I’ve had crazy pregnancy symptoms (barely being able to keep my eyes open, total scatterbrain and forgetting every other word of the English language) but I’ve been trying not to work myself up over them bc I know it could be all in my head.. now I’m CD32, no AF, no signs of her either. pregnancy test was BFN. I recently came off my IUD (august) so I’m not completely sure when I would be getting my period but my last cycle was around 30 days.

Should I write this off as me not being pregnant or should I keep testing? Is it likely that I can still get a positive even though today’s test was negative?