Should I have not posed nude for my friend/coworker??

I am a school teacher who is 33 and single and I have this friend Laura who who is the art teacher and she is 22 and going through her masters program right now and she asked me to pose nude for a sn ignment for one of her cles. I am afraid it may have affected our friendship now. She is a beautiful brunette but I think I saw an evil side of her when she was drawing me naked. I went to her house and got naked in her room that was a studio and when she walked in she started laughing hysterically and put her thumb and index finger about an inch apart. (what does that mean ladies?) and then throughout she kept giggling as I sat on the stool nude. I eventually got an an and then she laughed more asking me if it was 3 inches? (its bigger 3.5) She said I looked like a Macaca (monkey) with a little brown french fry. I am East Indian. Why do whites keep ridiculing us Indians? Should I end the friendship?