I used to use a combination of tampon and pad, because my periods were so heavy. This is what I had to do on school trips, just in case. Taking a travel size bag, like airline carry on instead of a regular purse, helps. Stash a waterproof bag, like a plastic shopping bag or laundry bag, and a spare set of underwater. Depending on the weather, I'd wear a long shirt untucked or tie a sweater around my waist. I've found that heat or deep pressure helps. The adhesive heat packs work. The back support girdle things that people in construction use always felt great. They are bulky, and can be visable under clothes so it depends on personal preference. But at night or in your own hotel/guest room it's good. My absolute go-to is a hot bath, as hot as you can comfortably make it. For cramps or migraines I'd have an ice pack on my face and be in the tub. I'd take Dramamine in addition to pain meds because it makes me drowsy, so I can sleep after.