Pregnancy cramps?

My fiancé and I had unprotected sex about seven days ago. Today I'm cramping and peeing like crazy. My period is due in three days, but I usually don't feel cramps until the day before I start. Ladies who have been pregnant before, did you cramp during implantation? If so, where did you feel the cramps and how long did they last? I honestly wouldn't mind being pregnant now... I'm almost 37 and we're getting married soon. I guess I'm also just afraid it's endometriosis or PCOS. I know there's nothing I can do but wait. I guess I'm just looking for some support here.