Question about possibly going into labor?

I will be 40 weeks this Friday, July 1. Tuesday when I went to the doctor I was 3cm dialated and 80% effaced. I have tried many thing to kick start labor...sex,walking (MILES AND MILES) pineapple, spicy food, chinease food, fresh pineapple, bouncing on an excercise ball and probably a lot of other things i cant think of right now. Well I am having tons of pressure..when i stand or walk i feel as if she is really low..and a few minutes ago i started getting these sharp pains in my lower abdomen. Could this be contractions or something else? Thanks for your help...I'm so ready for this baby girl to get here. :)