In the US, "negro" was once the accepted term; you'll hear it in old TV and radio or in literature, and all in the same tone as one might say "caucasian" or "asian". Eventually, we decided it wasn't so great and switched to "black". When you, in Spain, say "negro", it's the equivalent of us saying "black".
I don't think any of us say "afroamerican", but we do use "African American" even when the person in question is not American--it's kind of silly.
And yes, we say f*ck (censored because I don't remember the HN rules) constantly here too, but that's generally in a specific context: working on something with friends, out with other college students, etc. My friends and I, and most people I know, tend to not swear much around our elders or children; it's censored on TV because the audience is much wider than the couple friends you're hanging out with.