Hello, I Have Bilateral Stents Due To Kidney Failure, Have

hello, I have bilateral stents due to kidney failure, have had stents in for 4mths, went to kings island and got on a roller coaster ride just one, now I'm having blood flow, it was light when I got home and it picked up in volume and brightens the next day, with some tenderness in the area of the kidney's, the ride was high in speed and intensity, but I was told by my dr. that I could go and enjoy myself and get on rides, I'm nervous something is wrong should I just relax for a couple days?