HI, averyniceguy. I am hearing, but I learned ASL from a deaf employee.
I think part of the problem is the cultural difference between you and your hearing classmates. Deaf people tend to be "out there" with their questioning, and much more visual. Take for instance, the ASL word for "boobies". The fastest way to find out if that flirty girl was baring herself on the internet was to show her the picture. So you did. In English, of course, people dance around the question for quite a while before putting it out there.
In my mind, I see you making the sign for embarrassed, with a red face. Perhaps if you make that sign a few more times to the teacher, explaining that you sent the picture only to that one girl, and it was only to satisfy your curiosity, the teacher may invite you back.
http://www.lifeprint.com/asl101/pages-signs/e/embarrassed.htm