Implantation spotting??

Hi guys! I’ve never been pregnant. I have a low AMH and I’ve been on clomid for the past two cycles- we decided to save the meds this cycle until we got Hubbys SA results back. Of course they were perfect... (sigh) so we had sex like usual but I did not take the clomid... temping and OPKs confirmed I ovulated on my own- i have 21 day progesterone levels being drawn this afternoon. I am 6DPO and just went to the bathroom and had the tiniest bit of pink spotting... I’m trying to remain cautiously optimistic but my heart is also sinking. What do you ladies think? I have a 14 day luteal phase every single month with or without clomid so it’s strange that I would be starting so soon right?