Two Day Period please?

I just got my period (Not for the first time) and I am fairly young (13) but I have always been regular. Anyway I am going up boating in two days. And once your on that boat you can't get off until sundown really. I will be surrounded by family and friends and a very cute boy will be there and I couldn't just go into the water and insert a tampon and all. The water is clear T_T I will be out for about 13 hours and i need help on how to make my period go by faster and naturally because I do not do birth control or anything and I only have like 2 days so please help.