<human>: Can you succinctly summarize the text in 1-3 sentences?

I'm home for the summer from college, we live in the suburbs but make the drive to Houston Chinatown every two weeks or so for groceries. This week, I went with my parents and younger brother this time because I had a dentist appointment. Now, the dentist I used to have got in a little bit of trouble with the law (she's the one who took out all 4 of my wisdom teeth without anesthetics, see my post history) and "retired" back to China, we have a new dentist operating in the same facility now. Anyways, we drove there without incident and I started to get the general clean. It wasn't the actual doctor, but some assistant. She seemed new (intern, maybe?) and she was scraping my teeth with the slow precision of someone dismantling a bomb. She was leaning *so close* to my mouth, like, her nose was almost touching my front teeth (significant because Chinese noses). While she was scraping away, I just had a random thought... "I wonder what would happen if I just headbutted her right now". The look of unbroken concentration, the little wrinkle scar on her neck... I mean, she just looked... so headbuttable. 
  
I didn't end up headbutting her, but the more I thought about it, the more amused I became. I started by smiling, then giggling, then by little laughs that sounded more like "meeeeeeep" because the assistant still had her hands (and nose) in my mouth. Soon, I was stifling violent spasms of laughter and the dentist chair was shaking because I was failing. The doctor herself came in to see what was wrong, and at that exact moment, I could no longer hold in my mirth. I started wailing with laughter, and everyone in the office and waiting room could hear it. They ended up cutting the appointment short because I couldn't compose myself enough to let them finish. I ended up laughing for around 10 minutes, and that was more than enough for everyone in the stiff Chinese dentist office to think I was crazy. They told my mom (who was waiting outside) that I was "a very interesting daughter"... I have to go back in two weeks to fill a cavity. Cringing in a corner now.
<bot>: First time meeting my dentist, I think about headbutting her assistant and begin laugh loudly, everyone in the office thinks I'm insane.