Your initial ID doesn’t count towards the number of identifications that show in the bottom right on the observation page. If you later agree with someone, that seems to count. I’ll see if I can find the other thread about numbers not adding up.
Here’s a few previous discussions:
https://forum.inaturalist.org/t/discrepancy-in-identification-totals/29672
https://forum.inaturalist.org/t/observations-identifiers-count-discrepancies/17880
https://forum.inaturalist.org/t/discrepancy-in-observation-count-between-profile-page-and-explore-page/20009