Tastebuds are changing

I'm 7 weeks exactly today and this is my first pregnancy. I use to drink 1 cup of coffee every morning, but a week ago the thought of coffee sounded awful and I haven't had any since. This doesn't help the fact that I'm exhausted and pass out on the couch as soon as I get home from work. Anybody else notice they're not into some of their favorite foods/beverages anymore?