Is there any significant difference between saying 

> 
> I am/was **being** *adj*. (careless, busy, etc)...
> 
> 
> 

*[treating "am/was" as an auxiliary verb]*

and

> 
> I am/was *adj.* (careless, busy, etc)...
> 
> 
> 

Personally, I consider adding the word *being* a bit fussy but is there actually an effect of doing so?