Woman troubles, need advice!

im due to start my period on tuesday 14th April. I work out i ovulated around the 31st March. for a bout a week i have been having stomach cramps, lower down going across and a tightening feeling.
I want to know, if possible; if this is just very early period pains or could it be something else?
I normally don't have pains too much but i know things could have changed.
PLEASE HELP IF U CAN!