Shark Attack Dreams-needs help with interpretation?

For the past 1-2 months ive been having these shark attack dreams, the only thing is that none of these sharks attack me only the people around me (people i know and people i dont know). I get these dreams 1-2 maybe 3 times a week at the most. I had one today where i was at the beach and i was shopping for all these differnent types of bikini's. I remember this group of 8 people/swimmers going out into the ocean. A flash of black occured for a second then I hear screaming. I shake my head and look toward the beach shore and I spot a couple of the swimmers torn to shreads, bleeding all over the shore lines,body parts missing the sea full of red. A flash of black happens again and i love over and see a total of 6 people on shore dead, 4 women and 2 men. I see a boat with 2 people out in the ocean trying to find out what is going on and decideds to head back to short but something happens a wave comes down onto this little motor boat and takes it down. One of the propellers slashed one of the guys head in half and the other one barely makes it to shore. I remember setting up this experiement with a couple of people with diff sharks to figure out which one had killed these people. We had a station for diff sharks and made them attack these dummies so we can determine the bite marks. Then a flash of black happened again and then the beach started to flood (then i woke up). I get these dreams of sharks killing people and theres always a boat involved. I dont quite understand it all i know is that i get them 1-2 times a week and that im never being harmed. help?