Implantation????

So I'm anywhere from 8-13 DPO (Glow is not very accurate is what I've noticed and I ovulated earlier than it said on my chart) anyway, yesterday I felt a light, dull little ache like a cramp. I usually get them a week before AF but they are a bit more noticeable and more painful. I haven't had anything since yesterday. I know it's a stupid question but could that have been implantation?