To check out the GERD possibility, you might try taking Gaviscon Advance before bed. It's not identical to regular Gaviscon from the drugstore but instead a UK product available here via Amazon. It's a safe, natural formula that forms what they call a "raft" atop the stomach so that the contents don't leak upward into the esophagus overnight. It's a more natural alternative to omeprazole, also available OTC. Good luck.