Is it normal to have a conversation like this on a bus?

So, I was on the bus yesterday going home and some boys that usually take my bus were sitting behind me. I think they are 2 years older than me (Im 14). So they were talking about something and then all of a sudden one of the boys changed the subject and was like 'I got my penis measured yesterday!!! mines 17cm' and the boy next to him says "Only 17? Mines 19!' etc... subjects were about porn etc... So obviously we are on a bus and these 2 boys decide to talk about this topic when there are quite a few girls around!!! I felt quite uncomfortable sitting by myself in front of them so I moved to the back.. but is this normal??? to talk about how long your penis is on the bus? and competing on whos is longer?! It was one of the most awkward situations I have ever been in!