Sometimes the sentence doesn't really come out right. Last night I was heading out to a party and a friend in Japan texted me:
"You came back soon, didn't you?"
I couldn't tell if she was talking about me coming back from work early, or that I will come back from the party early. The first option was confusing because we were on a different topic. The second was hard to think of because of the two past simples. The sentence should have been:
"You will come back soon, won't you?"
Then I said "bad English", I can't understand. About an hour later my friend said "nevermind" and that was it until this morning. I was thinking about it and I felt very bad. I was thinking of it as a joke, but it probably wasn't very funny for them.
Learning is difficult, and it is easy to lose confidence. If we are learning the language ourselves then don't take criticism too harshly, but also take the feedback on board. If you know other who are learning, then make sure you are gentle, it's easy to hurt and be hurt when people's language skills are low.