My Friend Lied To My Family And Got My Mom Really Worried?

My friend came over over the weekend and had been telling us fake stories about her life that entire weekend. We all knew that they were fake the entire time. Well when ever she was about to leave she fell out of a tree in our yard and hurt her knee. So she came to school with a knee brace today, saying she broke her knee cap. I freaked out and I told my mom. My mom got REALLY upset and called her dad saying that she was SO sorry about her leg being hurt and going on and on about it. Her dad said that her knee was NOT broken and only slightly bruised and that she had been running around perfectly. It made every one feel so stressed. I was crying because I thought she would
Never be able to come over again!!! She cost so much stress to us for nothing! What should I do?