Mixed feeling....

Today, there is a bit of mixed feeling for the first time after started my doctoral studies for 5 months... is this really the kind of world I would like to be? For a moment, I felt that I was in between a bunch of Aliens! We are all speaking 'English', but for some reasons, the discourse (discussion, vocabulary, meaning) are soooooo different, so much so that I started to feel that I really did not belong to that world?! If I am in a business consulting seminar, or something... I felt that I am speaking the same 'language' with the presenter, and participants... but when I am sitting in between 14 business academia, I did not even feel like I am one of them, nor speaking the right terminology. It felt really like an idiot! I now start to have doubt, if this is really a worthy journey, or would it be better I just stay in my practical world which will bring more benefits to myself than a phD which has not much practical meaning to me... ponder!?