I have two questions about ways to refer to oneself in Japanese. Since they are so closely related I am posting both in the same thread but if anyone here strongly disagrees with this please let me know and I will split them up into two threads.
So here goes:
(1) I know one does not refer to oneself as XY-さん but rather as XY. But does this rule also apply to ちゃん? I'm asking because some of my friends call me ナッちゃん but using the general rule of just using my name this would leave me saying stuff like ナは今帰る。Since this sounds wrong to me I have been saying stuff like ナッちゃんは今帰る。
Is it normal/okay/natural to refer to oneself as XYちゃん?
I don't absolutely have to use ちゃん since I could just use my full name but that's more of a mouthful.
(2) I'm female and usually male individuals refer to themselves as 僕 when talking to me. Once I did a homestay and the host father referred to himself as 俺 when talking to me.
When someone says 俺 it makes me think that they are kind of common and I don't like it.
Is 俺 really a rough word to use when talking to someone of the other gender who is not an extremely close friend? Or is it good practice and I should not mind at all?