Your symptoms of acidity and abdominal pain are likely linked to your constipation. For relief, you can try an over-the-counter osmotic laxative like polyethylene glycol (MiraLAX) to safely ease bowel movements, alongside an H2 blocker like famotidine (Pepcid) to reduce stomach acid. Drink plenty of water and avoid stimulant laxatives, which can worsen abdominal cramps. Please consult a healthcare professional for a proper diagnosis. Seek immediate medical attention if you experience severe worsening of pain, vomiting, fever, or blood in your stool.