I included some results in my thesis that some other PhD students included in theirs. Is this plagiarism? I would like to ask you a question about my PhD thesis, which has already been defended. 

Part of my results were obtained in a university in another country. During my work, two of the PhD students there helped me and they have included these results in their theses. The problem is that I have also included these results in my PhD thesis, which was defended after theirs.

These results (included in my thesis, part of them in the thesis of one of the students and the other part in the thesis of the other student) are included in two publications. I am the first author of both of them, but I am given as equally contributed with one of the other PhD students in one of the paper and with the other PhD student in the other paper. 

Do you think that I can be accused in plagiarism or be in authorship conflict?
You should cite the other publications, your authorship involvement and your noted contribution status.

You should also note that you are presenting the complete result set while the cited publications each contain a part thereof. You should informally notify the other authors of your intentions - this may not change your course of action but it would be useful to know that they don't intend to contest any of your work.