Made a mess of RSS

In a rare fit of eagerness, I installed the FeedBurner plug-in and set up with my side-bar chicklet. It works fine.

But when I did that I made the assumption that the previous feed mydomain.com/feed would still operate. I see now that it doesn’t.
And so all my other RSS functions don’t function.

So I have three questions about this mess I’ve made:

1)What do I have to do to restore my RSS feed to what it once was so my previous subscribers still get my blog in their readers?

2) THEN, I’d like to either
a) re-direct that feed to FeedBurner
or
b) write a post about re-subscribing and direct people to the changed Feedburner uri.

and finally
3) I think what I really want to do is create a feed name for my domain, using a CNAME alias, which could remain constant and then if I wanted to change from FeedBurner to something else in the future (who knows?) I’d only have to change the pointer on the CNAME.
I realize this 3rd issue probably doesn’t fall under the the “jurisdiction” of this forum, but if by chance anyone had some suggestions on good help resources for this question, I’d be grateful. FeedBurner won’t support this kind of branding and my host can’t seem to help me figure out why the CNAME config I set up (more than 48 hrs ago) isn’t working.