There can be multiple reasons for your abdominal pain. Because of you ankylosing Spondylitis you must be taking painkillers long use of pain Killers of an causes gastric television and abdomen and they might cause this abdominal pain. You have mentioned other medicines also. I am unable to understand why you are taking those. Those are all related to respiratory problems and infection. Only take Pantosec-D 1 tab daily empty stomach. Do not use any other medications.
Next Steps
eat light food. if pain persists get and ultrasound abdomen done
Health Tips
avoid running and walk at a slow pace