You can pray as many as you like. I am currently praying Fr Heilmans Rosary Novena snd a daily Sacred Heart Novena and now I am adding St Andrew (not sure if the 15 times but I’ll do my best). I have a LOT of intentions as you probably figured out.
That's what I did last year. I know the prayer by heart now and I don't need a reminder because it pops into my head on and off throughout the day. Nevertheless, I'm going to set the image as my computer's wallpaper because I like it.