Up to the point where you ask for reassurance, you are correct. It probably only looks strange to you because you were previously doing it wrong. Of course, I'm American, so sorry, but I can't give you insight into any difference in British rules. I like to use the Owl at Purdue website when searching for punctuation rules. Your second question is a little more difficult. I couldn't answer you quickly, and out of curiosity, began to search for an answer. What you might want to search for is the use of ellipses in narration or in dialogue because the ellipses in academic writing indicates that part of a cited passage has been left out. In narrative writing, ellipses are used to indicate a pause, generally in dialogue. Here is a link that discusses the different punctuations and different uses for them. You will notice that it mentions a difference between British and American rules. It also gives many examples. https://fandom-grammar.livejournal.com/86156.html
As far as the punctuation of ellipses, a period or a comma would follow the three dots. In reference to the specific example you gave in your question, I would not separate the quotation as you have, not because you can't, but because it just reads rather strangely. But look at the examples, and you should get a better feel for how to use them.