Watersports in the summer?

Okay so in the summer i am going to be doing water sports for a week and I may have my period then. I have started to use tampons so i should be fine in the water...but i have a problem normally my period goes for two days and then i have a day of nothing and then another day and i have heard stories saying don't use a tampon if you are not on your period...however sometimes i might get a little bit of blood on the off day and if i am in the water..i should still be wearing a tampon right? Also if it leaks will people see it or is it not really noticable...my periods are moderate flow. I am worried they will leak especially with male instructors. If i am wearing a wetsuit will that help hide anything if it leaks? Also apart from the obvious if it leaks can you feel any digns...(not just see stuff if that happens)?...It is with my school so im sure loads o girls will be on theirs i am just really worried especially because we are sleeping in like gazebo type things and the bathrooms are not supposed to be very nice. Also if we are going out to the town on day and i am using tampons or pads...how do i hide them so nobody will see them...i know pockets but are there any othe rplaces you can hid them apart from bags? I know i must seem pretty oblivious to more experianced people but i am only a teenager and i want to know as much as possible so please fdotn call me mean things....Thankyou!