TIFU by calling my teacher a MILF

I walked into the lecture theatre together with my friend. We were 5 minutes early. I gestured for him to follow me to the seats right at the front. He looked at me puzzled, as I had never volunteered to sit in the first row. I told him to shut up for now and just follow me.

As we sat down at the first row, my friend pressed me for an answer. Realising the teacher was not here yet, I said something along the lines of 'Dude. Our teacher for this term is hella fine. Top bird I must say.'

My friend just laughed dismissively and repeated 'nah you can't be serious'. He noted that she was close to 40 and was just simply far too old. Feeling an urge to defend myself and my exquisite taste in women, I insisted (not exactly as my memory isn't perfect) 'she's 40 but she looks smoking hot, especially with those ballons at the back of her. She's a proper MILF.' Then, I added 'Plus, you know, closer to 40 means more naughty' (it is a Dan Bennett Quote btw, if you know who he is).

Right as I uttered these words out of my mouth, she stood up from underneath the tall lecture table. I was absolutely stunned. I just could not believe her eyes. I never saw her walking into the lecture theatre at all. Does this mean that she has been here all this while?

She shot me a look that was tough to describe. It was something between shock and horror. I kept my head low as I tried my best to avoid any and all eye contact. I was embarrassed. The lecture continued as per usual.

Later that afternoon, my form teacher asked me to meet my House Dean after morning assembly tomorrow. (PS. I am in high school, and we are all divided into 4 houses). She gave me a look that has disappointment written all over it. She did not elaborate much. She just briefly said this is regarding something that has happened today.

Fingers crossed that tomorrow will be fine

TL;DR I called my teacher a MILF, not knowing she was right infront of me.