Implantation bleeding???

Za

Today makes cd 38 for me, I typically have irregular cycles so I had to take provera to start my period. Well 5 days ago on cd 33 I experienced what I think was implantation bleeding. I saw it when I wiped, it was a medium pink color and I only had it the one time. I thought It was maybe my period starting because I had very mild cramping on cd 34 and 35 but here I am cd 38 and nothing. What do you ladies think? And when should I test??