Aw sis, yan talaga ang annoying, lalo na pag parang lahat ng kain mo ay naging sour, kahit ang tubig! A few of us had na same issue and honestly, it could be acid reflux, hormonal imbalance, or sometimes even nutrition-related, kaya worth it talaga na i-check mo with your doctor para ma-rule out kung ano talaga ang cause. In the meantime, try eating smaller meals, avoid very acidic or spicy foods, and drink plenty of water between meals instead of with food, marami sa mga kaibigan ko na relief dyan, pero ang most important talaga is makita mo ang doc para sure na okay ka lang.