Hi.. Thanks for the query.. As per your complain squeezing at the top of throat that comes with belching along with coughing is all pointing towards Gastroesophageal reflux disease or acid reflux.. It leads to excess mucous formation and also coughing.. It occurs more during lying down due to the supine position which eases flow of acid towards throat.. I would suggest you to consult a Gastroenterologist and get evaluated and a thorough clinical evaluation and investigations like upper G.I Endoscopy can help in diagnosis and treatment can be done accordingly.. You can be advised to take Proton Pump Inhibitors like Omeprazole or Pantoprazole.. Take antacids like Milk of magnesia.. Avoid spicy food and drink plenty of water.. Always take walk after meals and take your dinner atleast 2 hours before sleep.. You should sleep with head slightly raised as compared to feet.. Hope this helps.. Regards.