I have a similar problem: I deleted two posts from my blog, so now there is only one post when I view the blog (https://hermosawave.wordpress.com) – perfect.
But the feed still contains all three posts!
I am syndicating the feed to another web site, so I don’t think it is cached anywhere. I have also repeated this behavior on another wordpress blog. Maybe your server is caching it? (It’s been an hour though)
Any ideas? Thanks.