abdominal pain nausea and anxiety

Hi - my 7 year old daughter has been complaining of sharp pain in the lower abdomen, nausea and flatulence for months. She had a bacteria in the gut (Giardia) and was then put on a diet for months by the pediatric gastroenterologist doctor. The bacteria has now cleared but she is still in a lot of pain, more particularly when eating (or even before eating as she is worried about it too). She has become easily irritable and anxious as a result feels under a lot of stress. Any recommendation please as she has started school again in September and it's gone worse for her again. We tried to give her buscopan 10mg but she refuses to swallow them. Homeopathy is responding well for me so I am very eager to find something safer than buscopan. Thank you in advance!!