Hi!
Your dip isn't a huge dip below the coverline so I wouldn't be too worried, but it definately could be an implantation dip, I had one and ended up pregnant, but I have read that anyone can have one and not mean a thin, like it could just be an estrogen surge or something.
Also, you m/c in the beginning of august? Is this your first cycle since? Because it is best to wait at least one cycle to start trying again so your body can heal up better. I am still not back to normal and it has been 4 cycles! Good luck though!!!!