American visitors to the UK enjoy taking in the culture while they're here, and on Ben Zimmer's (of Language Log) most recent trip, he took in the controversies of this year's Celebrity Big Brother. For those of you who are in another country (for you can't avoid the news of it here), a woman who is a celebrity only for having lost a previous Big Brother got into trouble on CBB for alleged racist bullying of another celebrity. (I say 'alleged' because I haven't seen it myself, so shouldn't have an opinion on the matter.) She's quoted in the papers as having said I feel shit.
What she's done here is to use shit as an adjective. (Unless, of course, she was intending to say that she habitually handles f(a)eces. I really don't think she meant that.) Shit (or shite) and crap are found in the various places one finds adjectives in English--as in:
Now, this is not unheard of in AmE (as noted by Arnold Zwicky on the American Dialect Society list some time ago), but more typical AmE is to use shitty (or crappy) when one needs an adjective--or to use different grammatical constructions (as in 4b) in order to work around the nouniness of shit:
4. a. I feel shitty. b. I feel like shit.
5. remember how shitty you feel now
6. I'm having a shitty dayWhich is not to say that people don't say shitty in BrE too. The OED records the attributive (adjectival) use of shit first in Hunter Davies' 1968 book The Beatles. Shitty is first recorded in a 1924 letter by Ernest Hemingway.
This is ignoring, of course, the use of shit as a term of appreciation (as in it's the shit or shit dope and all that). That's always shit, not shitty, but it's also not what I'm talking about.
On shit versus BrE shite (rhymes with bite), the OED says that "The form shite now chiefly occurs as an occasional jocular or quasi-euphemistic variant." But most southern English people will tell you that shite is a northern and Scottish variant. I don't know what the Northerners and Scots say about it.