Period advice

Tomorrow I will go on horror quest with my friends, it will take some time. I've got a problem with my period this time, it is a bit heavier than usually (but no pain or something else, so everything is good). I won't be at home around 9-10 hours, so I'm not sure that there will be a chanse to control the situation well. I really don't know what should I do, can anyone help me?