Doing any kind of stretching/yoga type moves might help, or lay on your back, bring your knees up to your chest and hold, then straighten again, repeat a few times, see if that helps
Have you tried drinking flat coke/lemonade, this has helped me before (helps with the build up of acid in stomach which might be causing your trapped wind)
Also, see if you have any Rennie or any indigestion type tablets somewhere in the house
hope it goes soon!