Implantation bleeding or really short cycle?

I stopped Nuvaring a few months ago and my cycles have been 21 days, then 23 days, then 27days. This cycle I started spotting Wednesday afternoon (day 19). I didn’t detect an LH surge, so my friend thinks it’s just a short cycle and part of me regulating again. I normally spot for 48 hours before I bleed but it hasn’t happened. 48 hours later it stopped and its now Saturday morning with nothing.

Photo was taken when I got a blob of CM. That’s also the most blood I’ve had (it was only when I wiped). But was it too red to be implantation? Sorry for TMI.