Implantation bleeding ??

We are TTC. the other night i noticed light blood on the tissue.( that day i felt a pinching in my lower left side for two min)... thought perhaps it was implantantion.... next day nothing... this AM... bright red.. and light flow... its day 23 of my cycle... and im at such a loss ( last cycle was 36 days long) ..... guessing i wont be sure this is AF unless it keeps up for next 3-4 days? ... ive never had such a short cycle though... am feeling very discouraged. has  anyone else had implantation bleeding that was like a light period?