Is it my period or spotting?

So AF came on CD 25 which had me crushed bc we’ve been TTC for 6 months now and k had been fairly regular until the last few months.

2 months ago my cycle was 30 days. Last month 25-26

This month I started spotty yesterday and it’s been about 36 hours and still not enough to fill a tampon (I use a disc but can still tell the amount). Usually day 2-3 are super heavy so this is weird for me.

Thoughts. Had multiple negative tests prior to this so I know not to hope but what’s up?

I’m 35 trying for baby #2 and I’m overweight. We see fertility specialist for first time on Monday but I’m impatient and want an idea