I'm not in basic and to be honest I generally refuse to admit defeat to discomfort so push on regardless. Exercise/a run can often help with cramps.
As for how you could deal with it;
*waterbottle (although chances of being able to carry a waterbottle around? not likely I'm guessing )
*contraceptive pill - if not already on it thought about it? some brands you can back to back the packets too therefore no monthly (sometimes the occassional surprise mind!) and this can be done for months on end
*exercise (as above)