Period

HELP! I am going on vacation with my boyfriend and his family. I’m supposed to start my period while we are there. It’s a week long float trip down rivers and I am worried about how I will handle my period? I use tampons (super plus) but even then I still bleed through and I can’t wear a pad with my swimsuit. How will I change my tampon in the canoe without his family noticing? Any advice welcome!