Brown spotting, AF late, Neg HPT

Jenn • I'm 33 and currently pregnant with our first baby! Found out on June 8th we are expecting a BABY GIRL! Super excited!!
Hi,
I had a MC back in June, my cycle has been shorter but I can definitely tell when it's coming. We haven't been trying or preventing.  We just recently said we were going to try this month after my cycle but my cycle is not here. It's late, I just took a HPT a few min ago and it was negative. I've been brown spotting for 3 days now. On Sunday, I saw a little pink on one whipe but haven't seen it since. The brown spotting is so light that I could litterally wear the same panty liner all day (but I don't bc it's gross). Have anyone experience this before?? When should I test again or should I even test again??