hey there, I have PKD and have been flying since I was 6 months old :-) Never once have I ever had an issue.
I know that once when my mother was still in the Canadian Forces she had an opportunity to take the back seat in a F-16 trainer and her Neph said that if she was to pull more then 2-G then she would run the risk of a cyst rupturing.
You should be fine, have a great trip!!