For tummy cramps (or the runs) Chamomile tea works wonders- it stops the spasms in your tummy that cause so much pain. Double bag it for extreem measures... If you know what I mean. Roman Chamomile essential oil also works well (just rub it on your tummy). - Do not use the Roman Chamomile for too long or it will stop your bowels. Please note that if you have the runs, your body is telling you that you need to get rid of whatever is inside of you, so do no clog it up too much.
I have also found (from personal experience- with in 30 minutes) that homeopathic ARSENICUM ALBUM works very well for food poisoning (vomiting and the runs), also make sure to take some probiotics to get the good bacteria back.
take care of yourself, KT