Yes, it should not be a problem for you to swim with the dolphins as they are not attracted to blood. However, if you are swimming in open seas, you might attract sharks, so you should take a birth control pill to stop your period from occurring at that time (you can do this by taking your normal pill, and then instead of taking the sugar placebos, continue with a new pack.)
Sure! Just make sure you wear a tampon when you are swimming, especially if you are swimming in a ocean or sea, because the blood can attract sharks.
Yes you can swim with dolphins as long as you have a tampon but don't wear a pad because it can fall out. And watch out for sharks they love blood.