Перевод - Шведский-Английский - Det gor ont i mitt hjarta att behova saga nej men...

I think you need to put quotaton marks on 'no'.
I know there are not marks on the original, but it gets a little weird on the indirect speech.

I know internet isn't really a reference in itself but at this link, you got both of the ways to write it (I googled "to say no", or to say "no"?
Then Xini just respected the original way it was typed, I think...

The important is "will everybody who doesn't know swedish understand the meaning of this 'no' there?"

The best way to know it, is asking to an English expert, I think. But actually there is no need to ask, as she's got to evaluate this translation into English anyway.

I posted above, but I don't know Swedish and I'm not a native English speaker.I was just curious to know about this detail and about the right way to write it, but with the internet one gotta be carefull, not trusting everything that is writen on it (eg : my search about it and its results!)

No damage, and you were right to notify if you thought it is important, the English expert will rule and edit the way she wants, and maybe will let a note.

I must say that if it would be a translation into French, I wouldn't know too much about it and would have search as well, but this time using more referenced links, like "druide", which is a French Canadian and a very accurate one about French language. For the English language, I just don't know, because as I told you once, I'm not fluent in this language, which is much more difficult than many people think, although used in so many countries...

He did put the "" on the title, see?

It hurts my heart when I have to say "no" and you know why...

>>>discurs indirect

The title will help to understand; the text has no "" according to the original text.

It hurts in my heart that I have to say no but you know why. Are you really happy?