plan B

So I had unprotected sex and slipped up and we forgot to withdrawal. So now I'm in a dilemma trying to buy plan B. I have Kaiser and I emailed my doctor and they told me just to buy it over the counter which cost like 40dollars, which a pretty big price for me. I know it's cheaper than having a baby but do you guys have any solution on possibly getting it cheaper or free? One of my friends told me to go to planned parenthood and act like I don't got insurance? Any other recommendations?