Ovulation Cramps

Sarah • Babygirl born 10.10.15 Due with #2
So - Glow says I should ovulate Wednesday. I've taken OPKs everyday since Friday - the line is getting darker, but not positive yet. I'm having cramps & I've read some women get them, but they are traditionally on one side (the side the egg is being released from) - my cramps are centralized - anyone have this before or during ovulation?