Diarrhea, vomiting, nausea, headache, dizziness, stiff neck, bloated stomach and fever for a couple days. Went to the doctor and was diagnosed with gastroenteritis. Gave me meds (hyoscine methobromide, famotidine and paracetamol). Anyways, felt chest tighten, difficulty breathing and severe continuous pain (but it doesn t feel like heartburn). Possible side effects of the medicine?