If your 3 years' income met the requirements, then it should be fine. But I understand your fear re: your sister. Some applicants never received SA, but their files were transferred and went in-process.
Here's what you should do at once before you decide to withdraw your 2016 app:
1) Order GCMS notes. You can do it via
ATIP Online Request. It almost takes a month to process.
2) Try to link your app with MyCIC account. There are some tips I mentioned on
INFO sheet of the SS. It may not work for you if your app really did not pass the SA stage.
3) Contact IRCC Cell Centre (1-888-242-2100) and try to convince the agent with your dire situation to get more info on your app.