It is absolutely fine, given that you did both your grad and post grad from PTU. The process of WES evaluation has changed for PTU. You can no longer send the documents on your own. Only the university can send your transcripts.
Yes, it is okay to apply for both graduation and post-graduation transcripts from the same account of PTU. The only condition is that you should complete both the bachelor's and Master's degrees from the PTU. In recent years, the WES evaluation process has evolved and changed. According to the new process, the documents are not supposed to be changed by the students. Only the University is allowed to deliver the transcripts to the students. Hope this clears your doubts.