No. Shark attacks are supper rare. They'll only attack because usuallyy they will see you, or the victim, and think it is a fish or dolphin, their usuall prey. When a person thrashes around, it looks like an easy target to the shark. This is why it's supper important to swim slowly and carefully to shore when you see a shark, or just tred water if the shark comes nearer. If you want to avoid a shark attack, avoid going near the water when it's early morning or evening, this is the shark's favorit hunting time. Also avoid stormy wether, and 'fogged up' water, for a shark prefers this condition, for it relies more on smell, and the prey relies more on sight.
Not at all. I grew up swimming in the inlet that has had the most attacks in the US (Ponce Inlet/New Smyrna Beech, FL) and have never been bitten and I know no one who has been bitten either. I still go there when I visit home.
Shark bites are extremely uncommon. It is more likely to be bitten by a funnel web than a shark attacking you. just to add, if a shark is coming quite close to you and you feel uncomfortable, if possible, punch its nose as hard as possible then it would swim away. same goes with crocodiles