A part that really hurt about Teenage Dirtbag was that scene in the bathroom bit, when Thayer yells, “ No it wasn’t! It was only five seconds ago! Right?” 

And then he just starts counting; And they both kinda break down and just ugh.

If you think about it, it’s like he thinks that because he just wants to cling on to the fact that they still have something, that it isn’t something of the past.